Add Ansiesc plugin, replaces ANSI escape codes with Vim colours

This doesn't really do what I want but it's a start. It gives you a
command that runs on the current buffer. I'd like to do something
similar that can run in real-time (if at all possible).
Delete comment character when joining commented lines

This is something that really annoys me with commented lines, this
solution has been proposed as an addition to Tim Pope's vim-sensible
plugin but it's not certain that it'll make it in, so I'm adding it here
ahead of time.
Add Prettify and Uglify commands for Javascript

Reformats Javascript between compacted and expanded, requires you to
install node-uglifyjs. In future I might consider adding a toggle
function and bundling node-uglifyjs with this vimscript as a plugin.
Refactor autocommands

  * Move all my autocommands into the has('autocmd') check
  * Put all my autocommands into a group
  * autocmd! therefore only clears my own autocommands
  * Move this all to the end of the file

Being at the end of the file lets them use functions I've defined
earlier on.
Add autocommand to turn on English spell checking automatically

So far this is only enabled for filetypes where I type lots of English
quickly, usually forgetting to check the spelling, namely:
  * gitcommit
  * vimwiki