fixes #3205 - Extract and refactor report importing logic

This patch extracts all report importing logic into seperate importer and status classes.
long term this could allow:

1. aliases methods for async operations
2. different types of reports imports (based on reporting type).

fixes #1830 - auto assign puppet proxy if its not defined upon facts/reports event

fixes #3538 - workaround for broken #pluck on lower Rails versions

fixes #3486 - Make sure loading text is removed when chart data appears.

Fixes #3481 - Don't have to set a hostname for each interface, but it must be unique if it is set.

fixes #3256 - include members in usergroup show

refs #2792 - Adding comments to pxe templates

fixes #3267 - API v1 compatibility for /api/hosts

Fixes #3350 - Adds title on login page

fixes #3279 roles edit page is long and missing a filter