Add watchify and hot replacing of stores and components in server`s memory

[rdner]

Resolve #146.

• Completely remove assets management from Catberry (will be a separated plugin)
• Add watchify wrapper for browserify
• Replace gaze with chokidar
• No re-find/rebuild of the entire set of stores and modules on changes in debug mode, reload only a changed store/component

Known issues:

• Moving/Renaming component`s directory breaks watching for the component
• After removing cat-component.json from the components directory, the component is removed from the servers memory but its files will be still watched by chokidar (Unwatch is not unwatching folders paulmillr/chokidar#273)

[rdner]

Wrong destination branch.