Take into consideration more CDN assets for the Flex client:

- Added new option `localesDirectory` to language tag.
- Added `localesConfig` to language tag, removed domain guessing and make `locale.xml` external.
- Change the application initialisation order: load config.xml, then locale, then add MainApplicationShell to BigBlueButtonMainContainer if all is correctly processed.
- Added a new event LocaleChangeEvent.LOCALE_INIT.
- Added `videoProfilesConfig` property to VideoconfModule configuration.
- Fix skin name condition in SkinningService.
- Added new Options class: LayoutModuleOptions.