Removed configobj from test requirements

This module is not longer used by any code in the tree since
f164a60f15ea042b04b250ffc2001beda4f3e4bc.

Also removed a reference to the module from a README file.

Change-Id: I66c4935cb2e119bc96109416df7116d8c09e24e4
centralized router is incorrectly scheduled

When agent_mode=dvr only distributed routers should be
scheduled to that agent.  This change fixes this problem
by not allowing centralized routers to be scheduled
to an agent configured with agent_mode=dvr

Closes-bug: 1350667
Change-Id: I34e118535094520f2cee853f39d582a625acde20
Make ML2 ensure_dvr_port_binding more robust

There is a remote chance that this operation may
be prone to DB integrity errors, in case the binding
is attempted on the same port twice.

Ideally getter methods should not create, but this
is a common Neutron (anti)-pattern that would be
difficult to eradicate (at least in a single patch);
so for now let's make this code more defensive.

Related-bug: #1269131
Related-bug: #1335226

Change-Id: Ie6c57fd46f0752839814dbac5b14fae2364f973d
Fix DB Duplicate error when scheduling distributed routers

The error was caused by binding the router to an agent
candidate that was already selected during the scheduling
process.

A DB lookup was also saved by passing the router object
around; this led to a minor style cleanup.

Closes-bug: #1351123

Change-Id: Ib71a0140c8a7fbd5b230609d33487f8adba252e7
Remove reference to cisco_cfg_agent.ini from setup.cfg

No sample .ini file is included, causing install to fail.
Remove the reference for now.

Change-Id: I6dc88062cfd47ecee7ca9fc4e6ba64ce65d8ef07
Closes-bug: #1351466
Merge "centralized router is incorrectly scheduled"
Merge "Make ML2 ensure_dvr_port_binding more robust"
Merge "Remove reference to cisco_cfg_agent.ini from setup.cfg"
Merge "Removed configobj from test requirements"
Merge "Fix DB Duplicate error when scheduling distributed routers"