Don't show dismissed notifications again when items are removed

Closes #539

See merge request !600

Contacts, on your side

See merge request !594

Also fixed an issue with notifications alerting again when items
were removed.

Add an option to debug builds to create fake test data

Closes #703

See merge request !595

Disable PNG crunching for reproducibility

See merge request !596

Fix pink navigation drawer items with current support library

Closes #1051

See merge request !598

Upgrade Spongy Castle to 1.58

See merge request !597

This can help to prevent non-determinism introduced by the crunching
process.

More information:
https://gitlab.com/fdroid/fdroid-website/commit/e48f9f0773568d92ff764ad3cc79eed0ae2c497e

With enabled and disabled crunching,
the size of the signed release APK was 17809681 bytes.

Related to #164

Fix NPE when some RSS items don't have dates and add test

Closes #1064

See merge request !591

Add Norwegian Bokmål, Occitan (post 1500) and Serbian

See merge request !593

Fix crash when sharing a forum while it was just shared with us

Closes #1069

See merge request !592

by us → on your side

Don't add threaded messages to the UI before their parents

Closes #1024

See merge request !585

Remove old Bluetooth code and location permission

See merge request !584

Don't crash if the chosen ringtone can't be loaded

Closes #1044

See merge request !586

Upgrade Tor to 0.2.9.12

Closes #1060

See merge request !590

Libevent 2.0.22-stable, OpenSSL 1.0.2l and GeoIP 2017-09-06.

Keep the reply ID up to date in ThreadListActivity

Closes #1028

See merge request !587

Catch NPE when getting socket input/output streams

Closes #1042

See merge request !589

Works around a bug in Android 7, fixed in 7.1.

Catch IllegalArgumentException when parsing RSS feed

Closes #1040

See merge request !588