ASACORE-1181 fix SessionTest unit tests

Significant rewrite of the generic MultiPeerMultiSession test.

Change-Id: I2832f9f32984148d450acd4062248853d78fa194
Signed-off-by: Meggan Ehret <meggan@qeo.org>
Merge "ASACORE-1181 fix SessionTest unit tests" into RB14.12