Allow query logging

Reason: Each query which is executed through sqlalchemy are logged,
because engine had been initialized with parameter echo=True,
this flag cause security issue - logging insecure user credentials.

Changes:
- adding flag to guest config which allows to
unable/disable insecure/secure query logging,
default value for insecure logging - False;
- engine init parameter echo depends on config value

Closes-Bug: #1224700
Change-Id: I2e0e5970a981f16ce1abe96f012ed7618f57287a
Adding designate dns support to trove

Implements: blueprint designate-dnsaas-support

Change-Id: I69a8455595b519a6459f70efa8eef8a4013bd9f6
Corrects heat template for mysql.

Closes-Bug: #1253596

Change-Id: I3cce6b35fc40f4ff4cc45b04714067956fb1969d
Merge "Adding designate dns support to trove"
Merge "Allow query logging"