gl alias for pretiffied git logs; ghp alias for quick ghpages update;

GitHub pages alias is based on @leaverou workflow.

http://lea.verou.me/2011/10/easily-keep-gh-pages-in-sync-with-master/
Merge pull request #2 from kamilogorek/patch-1

gl alias for pretiffied git logs; ghp alias for quick ghpages update;