adding last-tag command to gitconfig

Author: Kevin McCulloch

gitconfig

@@ -4,3 +4,4 @@
   lg = log --graph --abbrev-commit --decorate --date=relative --format=format:'%C(bold blue)%h%C(reset) - %C(bold green)(%ar)%C(reset) %C(white)%s%C(reset) %C(dim white)- %an%C(reset)%C(bold yellow)%d%C(reset)'
   add = add -A
   commend = commit --amend --no-edit
+  last-tag = describe --abbrev=0