Add .gitignore for the generated unicode char name to codepoint database.
Refactor ops that depend on node modules to seperate files.
Refactor the runtime in nqp-runtime-core (the platform indepdent part) and nqp-runtime-node (the node.js specific part).

The nqp-runtime loads the right runtime (currently always nqp-runtime-core).
Fails some bugs due to a newly surfaced bug.