Allow WBE request transition timeout to be dynamic

To enable longer (or shorter) timeouts for a WBE submitted
request to transition out of the (PENDING, WAITING) states
allow the transition timeout that was previously set to 60
seconds to be provided as a WBE configuration option (it
still defaults to the previously fixed 60 seconds when it
is not provided).

Fixes bug 1356002

Change-Id: Idf384217004a334df03e2fff9150309fdfe08005
Merge "Allow WBE request transition timeout to be dynamic"