LBaaS UT: use constants vs magic numbers for http error codes

Closes-Bug: #1245388
Change-Id: I4192b577182891f6d777a5a5eac237c9961e41bb
Fix sqlalchemy DateTime type usage

In migration f9263d6df56_remove_dhcp_lease there is mistake in
DateTime type usage for mysql, used sa.DATETIME() instead of
sa.DateTime()

Closes-Bug: #1250405

Change-Id: I41fcd3babc64e3307895a92f03c7417577fa7b1d
Adds delete of a extra_dhcp_opt on a port

Add support for delete of extra_dhcp_opt(s) on a port. Where
[{'opt_name': 'opt_to_delete', 'opt_value': None}].

Closes-Bug: #1228008

Change-Id: I75baeff91575cac6546fe2cc6fcf7a0d8e92853f
Fix OVS agent reclaims local VLAN

If a port disappears on an OVS agent, the port is removed of the lvm
vif_ports list. And if it's the last port of the network on this agent,
the network local VLAN is reclaim.

Change-Id: I07e03107eb86a84eeb8e4d06f27a1d2fbd7cea57
Closes-Bug: #1252284
Adds tests, fixes Radware LBaaS driver as a result

Adding more tests for Radware LBaaS driver.
Adding new exception module for the Radware lbaas driver.
The base radware lbaas exception, called RadwareLBaasException,
Several specific exceptions for different failures.
Driver was changed for using new exceptions as well.
Changing the way OperationsHandler obtains context.
Always waiting 1 second before handling the operation
next time, to prevent busy-wait requests on vDirect.
Several code optimizations were done as well.

Change-Id: I15f7845fc2575eedb62c47d15ee6c1cea08e22f5
Closes-Bug: #1236741
Add request-id to log messages

request-id needs to be stored in thread local store to allow
openstack.common.log use request-id.
tenant_name and user_name are added to the context so that
they can be logged by customizing the log format.

Also replaces 'cxt' with 'ctx' in test_neutron_context.py.
Previously both 'ctx' and 'cxt' are used mixed in one file.

Change-Id: Ib921585e648e92491c1366bc0ad26a6ae71e2fc9
Partial-Bug: #1239923
Merge "Add request-id to log messages"
Merge "Adds tests, fixes Radware LBaaS driver as a result"
Merge "LBaaS UT: use constants vs magic numbers for http error codes"
Merge "Adds delete of a extra_dhcp_opt on a port"
Merge "Fix OVS agent reclaims local VLAN"
Merge "Fix sqlalchemy DateTime type usage"