Support Options method for CDA and CMA endpoints

Description

With this feature, the Options method for CDA (Content Delivery API) and CMA (Content Management API) endpoints is decorated adding full support for CORS (Cross-Origin Resource Sharing).

Other sites can send pre-flight request (Options request) to CDA and CMA endpoints. With this, CORS will also have support for the OAuth endpoints in the CD.OAuth package.

CD endpoints will return 'x-epi-continuation' in the 'Access-Control-Expose-Headers' header.