CMS-1807 Create reusable browse FilterPanel

Creating reusable BrowseFilterPanel written in TypeScript.
Also implementing filters for content and space manager.
CMS-1807 Create reusable browse FilterPanel

Add interface for facet data and add static method on to FilterSearchEvent
Merge pull request #293 from enonic/CMS-1807

CMS-1807 Create reusable browse FilterPanel