Gh1868 fix and enable mongo test

Add unit tests to verify that no empty region/ cycle/ shard can exist

1753 add unitest cases for ta_pos validation, expiration check

Comment out misleading log msgs.  GH #2016

Check signatures, transaction validation checks, and many other bug fixes

`authority_checker::satisfied` now catches `permission_query_exception`
specifically and returns false rather than propagating the exception to
the caller.

Also, fix checks on generated transactions.

Updated readme to reflect updated config folder locations

Feature/stricter auth checks

Enabled nodeos test.

Log number of missed blocks - #1987

EOSIO build CentOS

Fixed truncation overflow checks

Enhancement/dual node tester

Update bios boot script