Changes:

   * Ext JS transport (async-only)
   * fix loadingSchemes logic:

      * check for MANUAL_LOAD
      * check defaultZoneFile is valid string or object
   * make getRegionForTimezone a public method
   * implement loadZoneFileForTimezone
   * make shorter aliases for library (TzJs.tz)
Merge branch 'master' of https://github.com/jacobg/timezone-js