v0.2.0

This is the first public release, with several big interface changes:

1. Removed withReact(). Components now work without it!
2. Added .shinyInput suffix to components with interface modified to match vanilla Shiny inputs.
   The corresponding components without the suffix now expose unaltered React interface.
3. Changed naming convention to camelCase.
4. Added setInput() and triggerEvent() helpers.