gvimrc: change width to 89

149 is a weird width and less useful when given some thought.  Using a vertial
split to see two files simultaneously requires 160+ columns.  We end up with a
lot of whitespace that is slightly annoying.  Just resize to 89 columns, which
gives us a bit of wiggle room (numbers, context, colour column, etc).
gvimrc: tweak for macvim

Use Monaco on macvim and setup aliases for command+number to switch tabs
vimrc: tweak statusline
vimrc: add LLVMFormat command

This simply makes the indentation behave nicely for LLVM code.