OR-727 add a webserver awesomemodule to deploy then start then webserver

The webserver is augmented with addJSInjection and addCSSInjection which
create :
{
  'myModuleName': { 'myJs.js': ['myapp1, 'myapp2'] }
}
OR-727 add AwesomeModule for webrtc server and wsserver
OR-727 mock an awesome module for the servers configuration and the main esn application
OR-727 handle configuration.webserver||wsserver||webrtc.enabled property into their AwesomeModule
OR-727 change server.js to rely on the moduleManager
OR-727 add a webserver-wrapper AwesomeModule for external modules. It expose apis to modify the webserver
OR-727 fix styling and tests
OR-727 use linagora.esn.core.config instead of creating a new AwesomeModule
OR-727 remove not needed ESNApplication AwesomeModule
OR-727 fix linters
OR-727 use the contant ESN_MODULE_PREFIX where we can
OR-727 Rework server.js to handle errors from the AwesomeModuleManager
OR-728 create an utils.jade file which exports injectJSFromModules and injectCSSFromModules
OR-728 Integrate injections into all index.jade
OR-728 Inject js files and css files of modules intotemplates
(app.locals)

Conflicts:
	backend/webserver/index.js
Merge pull request #535 in OR/rse from ~SLEMAISTRE/rse:OR-728 to master

* commit '5719acb532e847be571feecae159968ec30dae9a':
  OR-728 Inject js files and css files of modules intotemplates (app.locals)
  OR-728 Integrate injections into all index.jade
  OR-728 create an utils.jade file which exports injectJSFromModules and injectCSSFromModules
  OR-727 Rework server.js to handle errors from the AwesomeModuleManager
  OR-727 use the contant ESN_MODULE_PREFIX where we can
  OR-727 fix linters
  OR-727 remove not needed ESNApplication AwesomeModule
  OR-727 use linagora.esn.core.config instead of creating a new AwesomeModule
  OR-727 fix styling and tests
  OR-727 add a webserver-wrapper AwesomeModule for external modules. It expose apis to modify the webserver
  OR-727 change server.js to rely on the moduleManager
  OR-727 handle configuration.webserver||wsserver||webrtc.enabled property into their AwesomeModule
  OR-727 mock an awesome module for the servers configuration and the main esn application
  OR-727 add AwesomeModule for webrtc server and wsserver
  OR-727 add a webserver awesomemodule to deploy then start then webserver