webadmin: Fix popup text, when dashboard is accessed 1st time

Rephrase popup message when dashboard is not
yet deployed.

Change-Id: I2a18685754334ebbf181e8c647c33cbb7ad77ecf
Bug-Url: https://bugzilla.redhat.com/1075948
Signed-off-by: Ravi Nori <rnori@redhat.com>