Vim: allow for per-host overrides file

I thought I was going to need this in order to get UltiSnips working on
two different machines, one with a Vim that links against Python 2 and
another linking against Python 3.

It turns out that with the latest UltiSnips, everything works fine on
both anyway. Nevertheless, I think this is a useful feature to have
around, so keeping it in.

Signed-off-by: Wincent Colaiuta <win@wincent.com>
Vim: update Pathogen bundle

The main motivation here is to get the latest UltiSnips, which includes
a necessary fix for Python support. The other things, however, are just
coming along for the ride.

Submodule changes in this commit:

  * .vim/bundle/fugitive 546a6bf...8f0b8ed (1):
    > Respect GIT_CEILING_DIRECTORIES

  * .vim/bundle/rails fcd1178...0f97e08 (3):
    > Fix detection of quoted default locale
    > Fix docs regarding :Rake and bundler.vim
    > Tighten down legacy ActionWebService match

  * .vim/bundle/ultisnips 1d903b2...ae611cc (7):
    > Merge pull request #121 from rudfol/master
    > Merge pull request #129 from lencioni/scss-import
    > Merge pull request #127 from nulpunkt/master
    > Merge pull request #126 from lencioni/scss
    > Merge pull request #123 from lencioni/improve-js-for-snippet
    > Do not use xrange since py3 does not define it.
    > Merge pull request #122 from lencioni/add-snippets

  * .vim/bundle/vim-textobj-rubyblock ae54af7...b5b84e4 (1):
    > Merge pull request #17 from shkm/patch-1

Signed-off-by: Wincent Colaiuta <win@wincent.com>