* Update module_utils.six to latest
We've been held back on the version of six we could use on the module
side to 1.4.x because of python-2.4 compatibility. Now that our minimum
is Python-2.6, we can update to the latest version of six in
module_utils and get rid of the second copy in lib/ansible/compat.
* updates all iosxr modules to support persistent socket
* adds iosxr action plugin to connect to device
* adds exec_command() to iosxr shared module
* fixes iosxr_config and iosxr_template local action
* update all unit test cases
* adds base test module for iosxr module testing
Toshio Kuratomi
Ricardo Carrillo Cruz
Peter Sprygada