Improve documentation for count_commits

Change-Id: I56767ffe22cdb67e0ac6b177a2a1a1e79f1742d0
diff --git a/bin/count_commits b/bin/count_commits
index e700424..d765c71 100755
--- a/bin/count_commits
+++ b/bin/count_commits
@@ -2,14 +2,17 @@
 use strict;
 use warnings;
 use Mojo::File qw'path';
+use Mojo::Util qw!extract_usage!;
 use feature 'say';
 use DateTime;
 use Getopt::Long;
 
 GetOptions (
   "help|h" => sub {
-    say "--quarter (Defaults to month)";
-    say "--current (Default to last)";
+    say "--quarter (show statistics for a quarter instead of a month)";
+    say "--current (show statistics for the current instead of the last unit)";
+    say "--user []";
+    say extract_usage;
     exit(0);
   },
   "quarter|q" => \(my $quarter),
@@ -97,8 +100,16 @@
 
 exit(0);
 
+__END__
+
 =pod
 
+=head1 SYNOPSIS
+
+  Usage: count_commits --quarter --current --user Akron
+
+=head1 DESCRIPTION
+
 This script will count and sum up all commits
 in all repositories listed in the configured repositories
 for a certain user in the current branches.
@@ -113,6 +124,8 @@
   /path/to/my/repo2
   ...
 
+The username has to be in the first line and written in square brackets.
+
 Two different time ranges are supported:
 
 Per default the last finished month