(#2569) simplifying code to avoid Eclipse CDT editor confusion, removing warnings and typos in comments

All samples use application style in android manifest instead of system calls in onCreate event now.

New versions tries to search library in arm-v7a and Manager packages only.

All constants moved to android independent header file.

Linker problems on armeabi-v7a+NEON with Android 2.2 fixed;

Issue #2506 Unnecessary log printouts in OpenCV::camera fixed;
Native camera for MIPS Android 4.1.1 added.
Build script for camera updated.

- Adding Android SDK/ADT r21 compatibility;
- fixing stl headers path for new ndk;
- fixing native API level for Android projects

Libinfo revision formating fix;
HW dependent VersionCode for Manager implemented.