Merge pull request #3699 from rsudev/crowdin_translations

crowdin: New translations
Add reference to crowdin translators
Version code

This time on release branch
Typo in version code
Another typo correction

Sorry again :(
fix #3703: NoSuchMethodError in Android < 2.3
fix #3704: NPE while attempting to download preview map
Update changelog for release
fix #3707: missing method in Android < 2.3
fix #3708: NPE in database cleaning

This happens only when the database is in bad shape, but prevents from
seeing the error message.
fix #3709: NPE in auto-complete

It looks like at least on Android 3.1 the `getCount()` method may be
called before results are published.
Restrict this version to Android >= 2.3
Partially revert < 2.3 compatibility mode

This reverts part of 46675dfdcb4c7b511b4c35e4a2242e47d4678fd4. However,
since this commit did some cleanup and simplifications, we keep them.
Remove now useless changes to RxJava
crowdin: New translations