feat: Upgrade to Bootstrap 4

BREAKING CHANGE:
See [Bootstrap v4 migration guide](https://getbootstrap.com/docs/4.0/migration/) to read about the most notable as well as breaking changes.

Author: mischah

__tests__/test-app.js

@@ -158,7 +158,6 @@ describe('Baumeister with default options', () => {
 			'src/assets/scss/_print.scss',
 			'src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_alerts.scss',
-			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_demoElements.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_footer.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_mixins.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_scaffolding.scss',
@@ -171,7 +170,6 @@ describe('Baumeister with default options', () => {
 		assert.fileContent([
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /testResponsiveHelpers/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /alerts/],
-			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /demoElements/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /footer/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /mixins/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /scaffolding/]
@@ -643,7 +641,6 @@ describe('Baumeister with less boilerplate code and handlebars enabled', () => {
 	it('should create just the essential Sass files', () => {
 		assert.noFile([
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_alerts.scss',
-			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_demoElements.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_footer.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_mixins.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_scaffolding.scss'
@@ -653,7 +650,6 @@ describe('Baumeister with less boilerplate code and handlebars enabled', () => {
 	it('should only import the essential Sass files within _' + _s.slugify(prompts.theme) + '.scss file', () => {
 		assert.noFileContent([
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /alerts"/],
-			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /demoElements"/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /footer"/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /mixins"/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /scaffolding"/]
@@ -722,7 +718,6 @@ describe('Baumeister with less boilerplate code and handlebars disabled', () =>
 	it('should create just the essential Sass files', () => {
 		assert.noFile([
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_alerts.scss',
-			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_demoElements.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_footer.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_ribbon.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_mixins.scss',
@@ -733,7 +728,6 @@ describe('Baumeister with less boilerplate code and handlebars disabled', () =>
 	it('should only import the essential Sass files within _' + _s.slugify(prompts.theme) + '.scss file', () => {
 		assert.noFileContent([
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /alerts"/],
-			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /demoElements"/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /footer"/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /mixins"/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /scaffolding"/]
@@ -870,7 +864,6 @@ describe('Baumeister using --yo-rc flag', () => {
 			'src/assets/scss/_print.scss',
 			'src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_alerts.scss',
-			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_demoElements.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_footer.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_mixins.scss',
 			'src/assets/scss/' + _s.slugify(prompts.theme) + '/_scaffolding.scss',
@@ -883,7 +876,6 @@ describe('Baumeister using --yo-rc flag', () => {
 		assert.fileContent([
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /testResponsiveHelpers/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /alerts/],
-			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /demoElements/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /footer/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /mixins/],
 			['src/assets/scss/_' + _s.slugify(prompts.theme) + '.scss', /scaffolding/]

app/index.js

@@ -512,12 +512,6 @@ module.exports = class extends Generator {
 					templateProps: this.templateProps
 				}
 			);
-			this.fs.copyTpl(
-				this.templatePath('src/assets/scss/_theme/_demoElements.scss'),
-				this.destinationPath('src/assets/scss/' + this.templateProps.theme + '/_demoElements.scss'), {
-					templateProps: this.templateProps
-				}
-			);
 			this.fs.copyTpl(
 				this.templatePath('src/assets/scss/_theme/_footer.scss'),
 				this.destinationPath('src/assets/scss/' + this.templateProps.theme + '/_footer.scss'), {

app/templates/_README.md

@@ -408,7 +408,6 @@ src/assets/scss
 ├── index.scss
 └── theme
     ├── _alerts.scss
-    ├── _demoElements.scss
     ├── _footer.scss
     ├── _mixins.scss
     ├── _scaffolding.scss

app/templates/_baumeister.json

@@ -4,11 +4,9 @@
   "bundleCSS": [],
   "bundleExternalJS": [
     "jquery",
-    "bootstrap-sass"
-  ],
-  "includeStaticFiles": [
-    "bootstrap-sass/assets/fonts/**/*"
+    "bootstrap"
   ],
+  "includeStaticFiles": [],
   "webpack": {
     "DefinePlugin": {
       "dev": {},

app/templates/_package.json

@@ -22,8 +22,9 @@
   },
   "private": true,
   "dependencies": {
-    "bootstrap-sass": "3.3.7",
-    "jquery": "3.3.1"
+    "bootstrap": "^4.0.0",
+    "jquery": "^3.3.1",
+    "popper.js": "^1.12.9"
   },
   "devDependencies": {
     "autoprefixer": "^7.2.6",