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