webadmin: adding '...' appender to text columns that overflow

Using TextOverflow.ELLIPSIS style property to achieve this.

Bug-Url: https://bugzilla.redhat.com/1122990
Bug-Url: https://bugzilla.redhat.com/1127674
Signed-off-by: Greg Sheremeta <gshereme@redhat.com>
Signed-off-by: Alona Kaplan <alkaplan@redhat.com>
Change-Id: I4978290d75286eb18358d97de1862c406ac8e89f