Big Upgrade/rewrite

[nmn]

An ongoing place to keep my work to overhaul the component, clean-up build process and add features and flexibility.

• Migrate build process from gulp to simple NPM scripts
  • build examples
  • Watch for changes while building examples
  • build for NPM (with Watch support)
  • Add dev server and livereload.
  • Add other scripts for verison bump etc.
  • remove the old gulp build process
• ignore all the built files from git
• add a .npmignore to include those files for npm (there was a suggestion of using a whitelist but that will be more painful)
• allow users to pass in customRenderLabel methods as a child instead.
  • allow passing custom optionRenderers
  • allow passing custom valueRenderers
    So, instead of:

<Select
    {...otherProps}
    optionRenderer={this.renderOption} />

You can do this:

<Select {...otherProps}>
    <Option>
        {this.renderOption}
    </Option>
</Select>

• Make more parts of the UI customizable.
  • Custom Component for OptionsList
  • Custom Component for Search field
  • Custom Component for Toolbars etc
  • Custom Component for SearchField

(probably not going to be handled in this PR)

• Any possible solution to make CSS better
• migrate the testing system to use expect-jsx, and airbnb/enzyme. (mocha stays on, wallaby.js I don't know anything about)

[nmn]

Obviously, don't merge this yet. Just leaving it here for discussion, code review etc.

[SylarRuby]

Id love this. I have to clear my rails cache then npm install for changes to show each and everytime. Its time consuming.

[nmn]

I've done a refactor to put menu in it's own component with list culling. This is just a proof-of-concept, and is causing some problems in the other cases.

I'm going to now start a complete re-write of React-Select. I'll look around for any work already started on that goal, so I don't duplicate work.

@JedWatson