BUG 15035: Fix reverse connections for render/data servers

URLs were not being parsed or generated correctly in a couple places
when setting up a reverse connection with render and data servers.

Change-Id: I4445573847184298387c5e61c32cd949080fd6dd
Additional baseline for TestColorHistogram.

Change-Id: I2fbacecee6e6b170f248d687e214e74b8b6af562
Merge topic 'pv-plot-bar-lut' into next

1611b378 Additional baseline for TestColorHistogram.
Merge topic '15035_reverse_connections_dsrs' into next

43bf1158 BUG 15035: Fix reverse connections for render/data servers