Convert module to use NAPI instead of Nan

binding.gyp

index.js

package.json

src/binding.cc

src/conversions.cc

src/conversions.h

src/language.cc

src/language.h

src/logger.cc

src/logger.h

src/node.cc

src/node.h

src/optional.h

src/parser.cc

src/parser.h

src/tree.cc

src/tree.h

src/tree_cursor.cc

src/tree_cursor.h

src/util.h