Document using Makefile.PL

Also bump minimum Perl version in Makefile.PL.

Author: Juerd

INSTALLING.md

@@ -25,7 +25,16 @@ Debian:  apt install libwww-perl libjson-perl
 Generic: cpan LWP::UserAgent JSON
 ```
 
-2. Clone the repository, run `./revbank` :)
+2. Clone the repository
+
+```sh
+git clone https://github.com/revspace/revbank.git
+cd revbank
+```
+
+RevBank can be executed without installing it (`./revbank`) or it can be
+installed using `perl Makefile.PL && make install`. The latter also gives you
+man pages.
 
 ## Configuring RevBank
 

Makefile.PL

@@ -1,4 +1,12 @@
-use v5.10;
+use v5.32;
+
+# NOTE: While it is possible to install RevBank with `make install` after
+# running this file, as is customary with Perl software, THIS IS NOT NECESSARY.
+#
+# RevBank also just runs from a cloned git repo: just run `./revbank`
+#
+# Makefile.PL was added because there are package builders that can use it.
+
 use ExtUtils::MakeMaker;
 WriteMakefile(
     NAME          => 'RevBank',