Use vital.vim for Dependencies

[svilenb]

Is it possible to use :Vitalize from vital.vim in order to remove tlib_vim and vim-addon-mw-utils as installation dependencies?

[ajzafar]

I neglected to comment on this because I already had plans to remove the tlib and mw-utils dependencies.

I've pushed the commits that make tlib optional.

Hopefully I can make the mw-utils changes happen soon enough.