Release 2.1

Created by: bochecha

And here's the latest ibus-cangjie release.

The changes in this version are:

• Add a link to the release tarballs in the README (Mathieu)
• Actually run the unit tests on « make check » (Anthony)
• Improve « make clean » (Anthony)
• Add install instructions for a few distributions (Mathieu)
• Improve the optionality of pycanberra (Mathieu)
• Fix the pt_BR translation (Mathieu)
• Reset sys.path to limit side effects on the unit tests (Mathieu)
• Ensure validity of the preferences UI file (Mathieu)
• Fix the UI file (Mathieu)

Users are highly encouraged to upgrade.

Happy Chinese New Year!