Adds scenario for IPv6 addresses

* Checks the way how  IPv6 addresses assigned to vNIC
* Eliminates hardcoded IPv4 subnet creation.
* Fixes problem with creating FIP for port with few addresses.
* Adds ping6 to remote_client

Partially implements: blueprint ipv6-api-testing-parity
Change-Id: I728edf0165ba47b6f8930f2fb3d08bd29cfbb317
Handle pagination keys in lister response

Right now, NetworkClientJSON.deserialize_list() returns the
first key-value pair from the lister response.

But the lister response might differ when pagination is enabled
with pagination_max_limit set to some value. There will be one
additional key-value pair like {resource}s-links: {href:, rel: ..},
which deserialize_list() does not handle

This patch attempts to fix this bug

Change-Id: Ic554abb0342288f9226cc358dc930cc150d098a2
Closes-bug: #1398811
Remove network debug

This commit removes all of the network debugging gorp usage from
tempest. These were added as a crutch over a year ago to enable
real neutron testing in the gate, which was impossible to debug
at the time. This debug info is an inherent layer violation in tempest
which is only supposed to be black-box and not care about any of the
underlying internals. It also assumes a single host environment and
that tempest is running on that machine, which is mostly specific to
the gate and devtest setups. Additionally the amount of output on a
failure is staggering to the point where keeping this around is
counter-productive. If we are unable to debug issues at this point
neutron needs to improve their logging so people can figure out what
failed.

Change-Id: Ia1ed4ab3cd2e4941fb072b3390f4859420989e74
Use assertIn to check for subnet membership

For dual stacked networks, the gateway port will have multiple subnets
associated

Change-Id: I450f896f29051921b011e1643f1a1e24ed82ac08
Merge "Use assertIn to check for subnet membership"
Merge "Handle pagination keys in lister response"
Merge "Remove network debug"
Merge "Adds scenario for IPv6 addresses"
Bump working version to 4

With the tempest-3 tag being published to signify the end of xml
testing in tempest we need to bump the working version to tempest-4
to indicate that the next tag will be 4.

Change-Id: I1fd12cb3e20692c60daa4eb19c6d876b00318d56
Merge branch 'master' of https://github.com/openstack/tempest