Link to directory of bootstrap

If we're already in a git directory, we should link the files here.

Use case: I add spf13-vim as a submodule of my dotfiles.
Set endpath properly

Set endpath to the location it's being called from so we can
check if we're in a git directory or not
Use vim-snippets instead of snipmate-snippets
Merge pull request #335 from benvds/3.0

Update snippets directory & docs
replace to new powerline
Merge pull request #339 from Gohan/fix_powerline

replace to new powerline
Merge pull request #328 from joshbetz/patch-1

Link to directory of bootstrap
Provide ability to revert back to the previous version of powerline
Add <leader>gw for :Gwrite in fugitive
Added the branch via bash variable to the git pull command when updating.
Merge pull request #353 from rraub/3.0

Added the branch via bash variable to the git pull command when updating...
Merge pull request #352 from johntyree/Gwrite

Add <leader>gw for :Gwrite in fugitive
Merge pull request #345 from mmikitka/toggle_powerline_version

Provide ability to revert back to the previous version of powerline
Update GitGutter after writing to the index.
Add GitGutter toggle similar to other git shortcuts.

All of the other shortcuts are related to fugitive, but I feel that it's best to
just put the "git-related" shortcuts together. <leader>gg shouldn't conflict
with any git commands other than grep, which probably much less frequently used.
Merge pull request #356 from johntyree/GitGutter

Update GitGutter after Gwrite
Merge remote-tracking branch 'upstream/3.0' into 3.0