Do not display success message on failure in web UI

https://fedorahosted.org/freeipa/ticket/3591
Move spec modifications from facet factories to pre_ops

Spec modifications in factories makes inheritance and extensibility more difficult.

Moving them to pre_ops allows modification of their output by other pre_ops.

https://fedorahosted.org/freeipa/ticket/3605
Unite and move facet pre_ops to related modules

Facet pre_ops defined in ./facet module were moved to modules where facet are actually defined. Moved pre_ops were united with the ones defined for the facets in these modules.

The move simplifies module dependencies - there is no reason to have general facet module dependent on specialized facet modules.

Pre_ops uniting makes the code simpler.

https://fedorahosted.org/freeipa/ticket/3605
Web UI: move ./_base/metadata_provider.js to ./metadata.js

Metadata provider is IPA specific object, not a framework object, so it should not be in _base directory.

https://fedorahosted.org/freeipa/ticket/3604