Add unit tests for VC manager APIs

Add unit tests for VC manager APIs

- Requirements:
VC manager APIs need to get test case for validation when it has to be
changed.

- Contents:
This patch adds new unit test cases for VC manager APIs. VC manager
provides only for platform certificated APIs, so it does not need to UTC
or ITC for release process. Thus, those APIs are not validated by any
test now. Through this patch, developers can validate the APIs if they
want it.

Change-Id: Iaffd992010954e330f6a0312e553e9ad04543108
Signed-off-by: Suyeon Hwang <stom.hwang@samsung.com>