urxvt: Add X11 Unicode font to font stack

It has nice symbols.
vim + tmux: Remove leading bit from title

In vim, it was the $USER@$HOST, and in tmux it was the instance number.
They were both a bit pointless
vim: Update some syntax and highlight files

Conceal styles were set everywhere, and syntax files update options.
Everything is now in its correct spot.

More conceal chars have been added for python, php.

concealcursor=nc is awesome
vim: filetypes can supply a name transform for tab titles

This is useful for python, where `__init__.py` is not a useful name.
`api/⊥` is more useful.
vim: Change window count indicator in tabs