Add code to follow ONAP API CVS guidelines

Add code to follow ONAP API CVS guidelines

Includes:
a) Added custom headers of versioning info into API response.
b) Added custom header of requestID into API response for fulfilling
   logging v1.2 requirements by copying from client's request header.
   If no requestID is contained in client's request header, API server
   will randomly generate one and include it in response header.
c) Added extension annotations into swagger to comply with swagger 2.0
   spec extension requirements posted in the table of ONAP API CVS
   guidelines wiki page.
d) Updated the package name of TOSCA model POJOs.

Issue-ID: POLICY-1270
Change-Id: Ia9e0f18c088604636008201fe5a149dc5fa21de3
Signed-off-by: Chenfei Gao <cgao@research.att.com>