Fixes #7525 - don't fail on structured facts

Fixes #7733 - Remove hosts.yml fixtures and use FactoryGirl instead

Refs #3809 - Use parentheses in method definitions

Fixes #6444 - add support for virtual NICs

Extend additional interface details refs #2240

NIC facts parsing change and we create interfaces in Foreman according
to facts we recieve.

Subclasses does not define their own attributes and serialize them to
attrs hash. All BMC attributes are extracted to separate columns so it's...

fixes #3272 - allow 'admin' account to be removed and replaced

[REFACTOR] fixes #2967 - refactored Fact Importer

Based on Dmitri Dolguikh <dmitri@appliedlogic.ca> original patch.

- renamed original fact_importer class to fact_parser class
- moved fact handling logic to its own fact_importer class
- fact importer now assumes single-value facts...