Config: major refactoring to support PNaCl
Config: major refactoring to support PNaCl

Maratyszcza/NNPACK,Maratyszcza/NNPACK,Maratyszcza/NNPACK,Maratyszcza/NNPACK,convercraft/NNPACK,convercraft/NNPACK,microblink/NNPACK,microblink/NNPACK,microblink/NNPACK,microblink/NNPACK,convercraft/NNPACK,convercraft/NNPACK