Merge branch 'es/first-contrib-tutorial'

A new tutorial targetting specifically aspiring git-core
developers.

* es/first-contrib-tutorial:
  doc: add some nit fixes to MyFirstContribution
  documentation: add anchors to MyFirstContribution
  documentation: add tutorial for first contribution

Author: gitster

Documentation/Makefile

@@ -76,6 +76,7 @@ SP_ARTICLES += howto/maintain-git
 API_DOCS = $(patsubst %.txt,%,$(filter-out technical/api-index-skel.txt technical/api-index.txt, $(wildcard technical/api-*.txt)))
 SP_ARTICLES += $(API_DOCS)
 
+TECH_DOCS += MyFirstContribution
 TECH_DOCS += SubmittingPatches
 TECH_DOCS += technical/hash-function-transition
 TECH_DOCS += technical/http-protocol