Initial version of node-API exposing for duktape scripts.
Tests fixed to comply with new function signatures.
Removed JSON-wrapper function inside vm. Now serialization is done via duktape-API.
Minor comment fix
Changed std::strings by value parameters to const refs.
Objectified callback cache
Fixed callback signaling on async version.
Rearranged project and streamlined data serialization.
Added tests for API and fixed a bug in serializing parameters
Renamed main entry point-file.
Minor
Merge pull request #1 from ndob/feature-api

Feature api