Merge pull request #9 from hpeng526/master

Chinese Simplified traslation
[37] Fix crash when saving InstallActivity
[38] Fix "done, go back" not doing anything in restored InstallActivity
[39] Add pull-to-refresh to MainActivity

* Using https://github.com/chrisbanes/Android-PullToRefresh
[40] Fix ByteArrayOutputStream leak in changelog download task
[41] Add "about" section and developer options to SettingsActivity
[42] Set developer options values when they are first activated
[43] Always setRefreshing(true) to PullToRefresh layout when refreshing
[44] Fix PullToRefresh layout being stuck in "refreshing"
[45] Add support for hammerhead and DTB
[46] Make "Ubuntu Touch is not available" string a bit clearer
[47] Prevent wrong update notification on reboot after multirom update
[48] Add ticker text to "Update available" notification
Fix typos in comment
[49] Don't create new toast for every developer options-related message
[50] Implement caching of MultiROM and Ubuntu Touch manifests
[51] Better fit text on status card and in install "terminal" on phones
[52] Use http cache fo changelogs too
[53] Download manifest from different server
Update strings.xml

removed three dots, just for aesthetical reason...