Rename apps to components; remove gulp from package.json

 - Rename apps to components
  - `lbclient/app-lbclient.js → lbclient/lbclient.js`
  - `server/app-server.js → server/server.js`
  - `rest/app-rest.js → rest/rest.js`

 - Rename config files
  - `server/app.json → server/config.json`
  - `server/app.local.js → server/config.local.js`

 - Upgrade juggler to 2.0.0-beta2

 - Remove gulp stuff from package.json

/to @ritch please review.
/cc @seanbrookes 

The patch depends on strongloop/loopback-boot#13