Unit tests review

[nanang]

Mainly focus on fixing spurious test results. This ticket is also a continuation of #1828.

[nanang]

In 5065:

Re #1842: Updated pjsua app to avoid stdout buffering, and also adjusted python tests accordingly.

[nanang]

In 5066:

Re #1842: Fixed build error on cmp_wav tool for python tests due to changed pjmedia format structure in 2.x.

[nanang]

In 5067:

Re #1842:

• Updated python test driver run.py to perform stdout polling using a dedicated thread, this will increase the robustness of pattern matcing class "Expect" and remove the possibility of stucked pjsua (due to output buffer full when no stdout read polling is done).
• Also updated other test driver and scenario accordingly.

[nanang]

In 5068:

Re #1842: Minor update on python test to reduce possibility of EADDRINUSE error in running pjsua.

[nanang]

In 5071:

Re #1842: Workaround for spurious failure in sipp/uac-reinvite-bad-via-branch.xml test, i.e: just retry the scenario. The failure is caused by race between SIPp sending re-INVITE vs transaction immediate termination (by SIP INVITE module when the session reaches CONFIRMED state).

[nanang]

In 5072:

Re #1842: Still on sipp/uac-reinvite-bad-via-branch.xml, fixed missing stuff in retry scenario, e.g: sequence number increment, To tag, wait for old tsx destroy.

[nanang]

In 5155:

Re #1842: Added automated test scenarios for Android and iOS 64-bit

[nanang]

In 5156:

Re #1842: Updated automated test scenarios to invoke 'make distclean' first.