FS-11211: [Verto-Communicator] Add turnServer and verto server fallback options -- FS side to only do relay as a last resort #resolve

Check value of sanity while looping over
switch_cache_db_get_db_handle_dsn() in switch_user_sql_thread.

Erroneous DLSR in received RTCP report could
cause RTT to be negative (RTT = A - DLSR - LSR).
Add check for this and prevent corruption
of statistics and estimations (estimator code used
bad RTT values).

This reverts commit 7cc6d5f99d16d2d63cb2548dd7b8345d579b7e9f.

This reverts commit 27389f29.

FS-10972: [Verto-Communicator] add (-y) parameter to the verto install script debian8-install.sh #resolve

This reverts commit 7944934d.
This reverts commit b120ddb9.
This reverts commit e8987b0d.