Added GoogleMap to sightseeing activity.

Added fragment with map to activity_sightseeing.xml.
Added OnCameraChangeListener to SightseeingActivity in order to keep zoom level in some bounds.
Merge remote-tracking branch 'upstream/android' into maps.

Changed LinearLayout to RelativeLayout and added transparent View to fix bug on Android 4.0.4 (after adding map navigation drawer was not visible).

Conflicts:
	res/layout/activity_sightseeing.xml
	src/com/blstream/myguide/SightseeingActivity.java
Added class for keeping settings and data from xml. Now SightseeingActivity uses it while rendering map.
Added few constants to Settings and few options to xml.
Few modifications:
- MyGuideApp - added class description, changed methods to synchronized, changed names of methods
- ParseXmlTask - added checking if data in MyGuideApp is null
- SightseeingActivity - fixed catching exceptions
Merge pull request #38 from illa/android

MYGUIDE-131