Provided and integrated a domain identity model Person.java with PL
identity MyUser.java, implemented a new Endpoint
X509Certificatev1Load.java for loading certs/keys from keystores and
designed a few new models to achieve the same.

Signed-off-by: girirajSharma <giriraj.sharma27@gmail.com>
Removed a redundant method (getUserByAlias()) from
IdentityModelUtil.java.

Signed-off-by: girirajSharma <giriraj.sharma27@gmail.com>
Merge pull request #4 from girirajsharma/master

Provided and integrated a domain identity model Person.java.