Remove Python 2.6 classifier

Neutron does not support Python 2.6 anymore starting with Kilo and might
not work correctly with it, so remove the classifier.

Change-Id: Ib7cddecdbec2c5152fe526bada6587129cf63ffd
Reject trailing whitespaces in IP address

Trailing whitespaces in IP address or CIDR pass API validation. These
whitespaces sometimes cause serious troubles. For instance, a trailing
CR code in allocation pools cause an ovs-agent to crash when calling
iptables. In this case, a tenant user's operation mistake affects whole
system.

By modifying _validate_no_whitespace() to reject data with whitespaces
in the beginning and the end, the IP address and CIDR validation
detects invalid attributes. The MAC address validation already rejects
these whitespaces.

Change-Id: Id4589236cfd44c2fd5956c5ab4ab6871381a0c34
Closes-Bug: #1393329
Fix floating-ips in error state in dvr mode

Before this fix an exception was raised when
creating the veth between the fip namespace and
the qrouter namespace when the veth was already
present.
This fix add a check to only create the veth if
not present.

Change-Id: Iefea9778223aac885bedfdacfdeacfce74776333
Closes-Bug: #1376013
Remove unused xml constants

Change-Id: I38d720095a2fe703e55d895350e3894c35649d4e
Merge "Remove unused xml constants"
Merge "Remove Python 2.6 classifier"
Merge "Reject trailing whitespaces in IP address"
Merge "Fix floating-ips in error state in dvr mode"
Merge branch 'master' of https://github.com/openstack/quantum