Update vim fuction names

To conform with new vim patch (Patch 7.4.260) which specifies that g: functions need to start with a capital letters.

Just updated vim to 7.4.273 and plugin freaked out. Changed all g:functions to CamelCase

Patch details are here: https://groups.google.com/forum/#!topic/vim_dev/M4_E1QhXVxA