Release 2.2

[bochecha]

Here's a minor release.

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Bug Fixes

• Fixed using the numpad to commit candidates. (Mathieu)

  Docs Improvements

• Added installation instructions for Arch Linux. (Antony)
• Removed an obsolete (and confusing) notice about release tarballs. (Mathieu)

  Testing improvements

• Get Travis CI to build against the 1.x branch of libcangjie and pycangjie, as their master branch has now broken the API in a way that ibus-cangjie 1.x doesn't build against it any more. (Mathieu)
• Use the in-memory GSettings backend for the tests, so avoid any undesired side-effects from the running environment. (Mathieu)

[bochecha]

Oops, I made a mistake here!

This shouldn't be merged into master, but into the 1.x branch.

Closing, I'll reopen correctly.