Update submodules

  git submodule foreach git checkout master && git pull
Add Ultisnips vim plugin
Remove unused filetype config

I never use C, Objective-C, or Prolog, so I am removing these bits of
configuration from my .vimrc file.
Split up .vimrc

In the interest of cleaning up my .vimrc, I want to organize this a bit
better. Vim allows for the organization of filetype-specific
configuration in the ftplugin directory. I may as well take advantage of
this feature.

I am also abusing the plugin directory as a place to stick my settings,
since it is autoloaded and pathogen takes care of my actual vim plugins.

Some adjustments were made to the configuration at the same time,
inspired by Wincent's configuration:

  https://github.com/wincent/wincent
Change UltiSnips triggers, add JS snippet

I want traveling between snippet placeholders to be more natural, so I
changed the triggers to be tab and shift+tab.

At the same time, I added a basic JS snippet for defining a function.
Add HAML, Jasmine, JavaScript snippets

I found some snippets that I think may end up being useful.

Jasmine snippets borrowed from Wincent[1], and HAML and JS snippets
borrowed from ultisnips-snippets[2].

[1]: https://github.com/wincent/wincent/blob/master/.vim/UltiSnips/jasmine.snippets
[2]: https://github.com/aalvarado/ultisnips-snippets