StarSpace native bindings for ⬡.js

• Boost is required according to StarSpace (Should I include boost in this project and let CI (travis) build binaries !?)
• gcc-4.6.3 or newer or clang-3.3 or newer
• if you wish to run the unit tests in src directory, google test is required and its path needs to be specified in 'TEST_INCLUDES' in the makefile.