git: Add aur-package template folder

Use `init.templateDir` to use this.

.local/share/git/templates/aur-package/hooks/pre-commit

@@ -0,0 +1,20 @@
+#!/bin/sh
+#
+# An hook script to verify what is about to be committed.
+# Called by "git commit" with no arguments. The hook should exit with non-zero
+# status after issuing an appropriate message if it wants to stop the commit.
+
+if git rev-parse --verify HEAD >/dev/null 2>&1
+then
+	against=HEAD
+else
+	# Initial commit: diff against an empty tree object
+	against=$(git hash-object -t tree /dev/null)
+fi
+
+# Redirect output to stderr.
+exec 1>&2
+
+# Regenerate .SRCINFO
+makepkg --printsrcinfo >.SRCINFO
+git add .SRCINFO