The GET /os-migrations API take a migration_type and source_compute
filter parameter on the request since the v2.0 API. This adds support
for specifying those parameters in the "nova migration-list" CLI
and related MigrationManager.list() python API binding methods.
A functional test is added which will cover the new options on all
three of the decorated do_migration_list shell methods with lower
bounds on 2.1, 2.59 and 2.66. Since the only type of migration we
can safely generate in a single-node CI job is a resize the test
does a resize. As such, _pick_alternate_flavor is moved into the
base test class for re-use.
Implements blueprint more-migration-list-filters
Change-Id: I4be9a06df3e0d40d3990d067ce112247a81b45b4
0e7c99c8ea