Fixes #9878 - refresh external usergroup on API manipulation

Fixes #8812 - Pass model type so search_for is called on Host

At least on version 1.6.1, the absence of this second parameter leads to a
runtime crash when it's time to validate if the current user (non-admin) is
allowed to perform a power operation on given a host via the APIv2....

Fixes #9921 - specify requirements on apidoc params for NICs

Fixes #8890 - Allow selection of plaintext "encryption" method for root password

Fixes #7378 - fixed API lookup keys filters

refs #9877 - s/variable/class parameter/ on param :override

fixes #9877 - Add descriptions to smart_class_parameters in api/v2

fixes #9823 - Add description to smart variables

Fixes #9723 - missing owner_type in host api docs

Fixes #9657 - merge NICs from compute profile in host create API

- updated api docs for hosts and interfaces
- host create/update api actions now merge interfaces from compute
profiles
- NIC type mapping extracted into a separate class
- return full host detail after host update