Install Ultisnip and other changes

* Use Ultisnip, instead of snipmate
* Change octave references to matlab
* Refactor file indent lines into a function
Filetype on before loading ultisnips

UltiSnips need filetype on.
See https://github.com/gmarik/vundle/issues/176
about the filetype issue with vundle.
Add Ultisnips snippets