v1.0.0 minimal core edition

- Made Rebelle into a minimal core that loads:
  * a user settings file (~/.rebelle/index.js / ~/.rebelle/package.json)
  * loads plugins (~/.rebelle/node_modules/rebelle-*/
  * rc-files (~/.rebellerc.js / path/to/project/.rebellerc.js)
  * the current project, as previous

- Removed hot code reloading, please write a module if this is needed