Chang my git config to use credentals caching.

Since I can not use ssh to connect to github from work. I needed
to set up credential caching so that I do not have to alwals type in my
long complex password.
Add fetch -v, and status -bs git aliases
Add autoinstall of my favorite emacs packages. Disable yas in org-mode.

Using prelude to auto install all my favorite packages on emacs startup
if they are not already installed. Also yassnipet was sometimes expanding
unwanted stuff in org-mode, so using the hook i disabled it.