Streamline template creation flows - update

Update:
1. Disable the "Remote ISO Image" option temporarily.
2. Select ISOs by clicking in the box.

Signed-off-by: Xin Ding <xinding@linux.vnet.ibm.com>
Enable the template_create test with non-root account

Use the "test:///default" as the url to Model object instead
to enable non-root account test

Signed-off-by: Shu Ming <shuming@linux.vnet.ibm.com>