Don't check git status in prompt, just branch name

Checking the git status in the prompt results in a huge slowdown on
large projects. Getting the branch name is fast, and it's enough for me
given that it tells me:

    - I'm in a git repo
    - What branch I'm on

Those are really the things that I want to know in most situations.
Upgrade pshop to THE CLOUD
Don't pollute the Startify list with help files
.vimrc: give the header and footer top margin

 -------------------        -   -        --------------------
     ----------------       -----       -----------------
       -----------------------------------------------
        ---------------------------------------------
         -------------------------------------------
        ---------------------------------------------
                         -----------
                            -----
                             ---
                              -