Fixed vim alias.

- Only set vim alias if MacVim is installed (using homebrew or not)
Updated vim-slim submodule.
Color improvement
Added ,gt html tidy command
Sprintly alias
Merge pull request #236 from giorni/slim-update

Updated vim-slim submodule.
Merge pull request #235 from rafaelregis/fix_vim_alias

Fixed vim alias.
Add quickfixsigns module - shows which lines changed
Update pismute's configuration