Remove uniq function (fixes joseotaviorf#22)

Merge branch 'develop'

[Fixes joseotaviorf#19,20,21]

Merge branch 'develop' (fixes joseotaviorf#17)

Damn old version of vim (fixes joseotaviorf#15)

OS X provided vim, although is 7.3, is crap.

It's sort() function takes only 2 arguments, and later versions of vim
accept 3 arguments which broke the damn plugin, because the author uses
MacVim (and so should you :).

Minor changes to readme for last merges