Rename AndroidManager::targetSDK to buildTargetSDK

There are 3 different sdk settings:
- The minimum sdk setting from the AndroidManifest.xml
- The target sdk setting from the AndroidManifest.xml
- The target sdk setting from the project.properties file

The last one is now called buildTargetSDK, since it only affects the
build.

Change-Id: I373d925a45088ff0cf8a8e0b22cf9744e571eeb1
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
Android: Use minimum sdk instead of build target sdk to filter devices

Task-number: QTCREATORBUG-9662
Change-Id: I3a5b3493bc8ef48bd23d014e86eef45185f3c17e
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
Fix compilation with Qt 4.

Change-Id: I9217eb6695b9e48579f66b7fd8709c84806ffb66
Reviewed-by: Daniel Teske <daniel.teske@digia.com>