.curlrc: Disguise as IE 9 on Windows 7

This matches the `.wgetrc` settings.
.aliases: Add `timer`

`timer` can be used as a stopwatch.

Hat tip: https://twitter.com/tow8ie/status/360077953238962176
.gitconfig: Improve display of astral Unicode symbols in diffs

Thanks to @holman for the tip: https://speakerdeck.com/holman/more-git-and-github-secrets?slide=38
Merge branch 'master' of https://github.com/mathiasbynens/dotfiles

# By Mathias Bynens (2) and Simon Owen Design (1)
# Via Mathias Bynens
* 'master' of https://github.com/mathiasbynens/dotfiles:
  .gitconfig: Improve display of astral Unicode symbols in diffs
  .aliases: Add `timer`
  .curlrc: Disguise as IE 9 on Windows 7