Opencaching integration with oc11xml api

Implements load of cache details, coordinate search and viewport search
for opencaching.de based on oc11xml api
Fix #2332. Add error handling for failed favorite changes
Merge pull request #2334 from campbeb/fix2332

Fix #2332. Add error handling for failed favorite changes
fix #2328: Have a wrapper around Matcher to avoid String related memory
issues
fix #2250: "Scan QR code" doesn't work anymore
Update ChangeLog for #2250 fixing
Merge branch 'release' into upstream

Conflicts:
	main/res/values/strings.xml
	main/src/cgeo/geocaching/connector/IConnector.java
	main/src/cgeo/geocaching/connector/gc/GCConnector.java
Merge pull request #2311 from rsudev/OCde2

Opencaching integration with oc11xml api
fix #2336: support for secondary users in multi-users mode

This will allow c:geo to work correctly in multi-users mode as long as
the default settings (keep files on internal sd card or phone memory)
are used.

Files stored on secondary memory will still be shared between users,
but the permissions should be allowing that.
Update ChangeLog about #2336
Merge branch 'release' into upstream

Conflicts:
	main/res/values/strings.xml
fix #2337 NPE in cache list when leaving activity early
Merge remote-tracking branch 'origin/release'