.osx: Hide Safari’s sidebar in Top Sites by default

Closes #296.
.gitconfig: Add aliases to find branches/tags/commits

Closes #304.
bin: Make `httpcompression` prevent caching

In some cases, intermediate proxies ignore the `Content-Encoding` header
altogether.

Sending `Cache-Control no-cache` as a request header solves this problem
by forcing validation of the resources in the intermediate proxies,
thereby, ensuring that every request is fetched from the origin server.

Ref. alrra/dotfiles#2. Closes #308.
init: Fix typo in Sublime Text settings
.osx: Hide some menu bar icons in OS X 10.9 Mavericks

Kudos to @kevinSuttle for finding the appropriate `plist` file!
https://github.com/mathiasbynens/dotfiles/issues/305#issuecomment-30102827

Ref. #305.
.osx: Delete some old commands that no longer work

These commands only work on outdated versions of OS X.

Ref. #305.
.gitconfig: Add `dm` alias

`git dm` deletes local branches that have been merged with master.

Closes #309.
init: Tweak Sublime Text settings
.osx: Add Activity Monitor settings
.osx: Add Finder ‘Get Info’ settings
.osx: Display Bluetooth icon in menu bar
README: Credit @kevinSuttle
.osx: Set Desktop as the default location for new Finder windows

Closes #285.
.aliases: Add `jsc` alias

Useful for testing code in JavaScriptCore.

Hat tip: https://twitter.com/RussB/status/420409644117262336 (via @rauschma)
.functions: Make `np` remove `node_modules`

This lets you catch cases where you forgot to add a dependency to `package.json`.

Closes #321.
.osx: Support multiple `systemuiserver` pref files

Closes #319.
Brewfile: Install `p7zip` (i.e. `7z` etc.)
.osx: Kill `cfprefsd` after changing preferences

As of OS X 10.9 this is necessary to make sure the changes persist.

Closes #330.
Brewfile: Install ImageMagick with WebP support