rollback to appcompat v20

v21 appears to just not be ready for production given the bugs.
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Don't completely disable GCM.

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Updated translations.

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Bump version to 2.3.1

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The future is the other direction.

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Add callback method parameter to axolotl decrypt functions.

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Guard against fragment disappearing before callback.

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Do thread trimming as JobManager job rather than AsyncTask.

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reorder window feature requests in MediaPreviewActivity

ActionBar is initialized in a different way by AppCompat v20 compared to
ABS or v21 even...
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fix for ringtone selection with android-support-v4-preferencefragment
Try to fix LGE menu button NPEs
fix based on https://code.google.com/p/android/issues/detail?id=78154

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Revert "Try to fix LGE menu button NPEs"

This reverts commit f3a3aaca6051b5ae464c026ff8d72e51a1d5a8a6.
compat actionbar bg for dark theme

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Bump version to 2.3.2

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PushNetworkException for network errors on external downloads.

Closes #2112
Fixes #1264

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Minor cleanup.

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Move directory refresh from a service over to a job.

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Move JobManager to external project and dependency.

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Display 'me' for device's local number in group membership list.

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Fixes #1494
Closes #1505
move log submission to new library

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Closes #1655