Adding go-lang plugin to virmc
Removing tmp as backupdir

Backupdir doesn't play nice with Vim on Mac, this is weird, I need to
spend more time on this, for now, I am not really worried about swap
files
Using indentation for foldlevel.

The trade off is understood, it would be a hell of a pain when I am
writing Go, C or JavaScript. Ideally should move to a syntax based
folding, where the folding property is specified in the syntax of the
language.