Added form abstract factory.

Change-Id: I071cf7b8e41d3f7f06f942650dc6f8a3d2215cba
Remove redundant "else" statement and redundant condition in factory
method.

Change-Id: I4a3bb387e4f63c5aa70519923ad3680c8ae5e5b0
Added injection of FormElementManager.

Change-Id: Ia85eab01106afa54e8156dadb9fece15d73e9ae8
Fixed coding style. 
Minor improvements in abstract factory methods.

Change-Id: Ic6d1de0efede8780ff6d50126b98b50dee5fa5fb
Added test case for FormAbstractServiceFactory

Change-Id: I93522febd9f4c61286a2bce36bf3a1333a54e1ae
Merge pull request #3932 from stephanoff/develop-form

Added form abstract factory
Merge branch 'feature/3932' into develop

Close #3932