v0.2.1

Breaking changes:

• Value object initializer bind is now a dynamic instead of a static method of the exports object returned by require('nbind')

Other changes:

• Fix loading modules from browsers and add basic TypeScript definitions.
• Add tool to copy compiled asm.js output to a target directory.
• Avoid losing errors from asm.js init.
• Fix overriding the toString method on Emscripten target.
• Support passing pointers on Emscripten target.
• Fix loading asm.js code without running "npm link nbind".
• Rewrite documentation.