Changes

Bump Android NDK to 'android-ndk-r8d' - Note: '-fno-use-linker-plugin' is required (?!)

Cleanup GlueGen config 'ExtendedInterfaceSymbols*'

Semantics Change:
  ExtendedInterfaceSymbolsOnly was used for implementation generation only,
  which is considered a bug!

- ExtendedInterfaceSymbolsIgnore C.java
  - Ignore symbols in C.java for interface generation
- ExtendedInterfaceSymbolsOnly C.java
  - Only use symbols in C.java for interface generation
- ExtendedImplementationSymbolsIgnore C.java
  - Ignore symbols in C.java for implementation generation
- ExtendedImplementationSymbolsOnly C.java
  - Only use symbols in C.java for implementation generation
- ExtendedIntfAndImplSymbolsIgnore C.java
  - Ignore symbols in C.java for interface and implementation generation
- ExtendedIntfAndImplSymbolsOnly C.java
  - Only use symbols in C.java for interface and implementation generation

Fix comments in gluegen-cpptasks-android* config file

Android: Cleanup ClassLoaderUtil/LauncherUtil - Using cached parent ClassLoader for SYS-Packages w/ native libs, and non cached child ClassLoader for USR-Packages

Android's Dalvik VM, like a JVM, cannot load a native library from one location by multiple ClassLoader.

Since we don't like to hardcode the system-packages, as it was before, i.e. "com.jogamp.common", "javax.media.opengl",
we need to either copy the libs or use parenting of cached ClassLoader.
The latter is chosen, since it's faster and uses less resources.

- System-packages are passed through from the user 'List<String> LauncherUtil.BaseActivityLauncher::getSysPackages()'
  to the ActivityLauncher, which instantiates the ClassLoader.

- No more hard-reference the system-packages in ClassLoaderUtil ("com.jogamp.common", "javax.media.opengl"),
  just use the new user provided system-packages.

- The system-packages denominate a hash-key for caching, a new ClassLoader is created and mapped
  if it does not yet exist.

- A non-chached user-packages ClassLoader is created using the cached system-packages ClassLoader as it's parent.

IOUtil.copyStream2ByteBuffer: read while numRead > -1 ; add variant w/ initialCapcity

IOUtil.copyStream2ByteBuffer: Turns out on Android, no -1 (EOS) is returned - relax loop-condition (hope thats ok)