Fix mappings bound to wrong leader key

I messed up some mappings because I didnt realize that the leader key was bound to , after the init directory is loaded.
Allow <tab> to expand snippets again
Use newer maintained version of vim-snipmate
Add vim-snippets to pick up many new snippets
Remove snippets that have vim-snippets versions
Merge pull request #24 from pivotalcommon/fix-snippets

Fix snippets
Improve experience for golang

This includes not showing whitespace characters, running go fmt on save, and using tabs instead of spaces for go files