Issue 467 filter for unplaced elements

[andreasweishaupt]

• search bar in unplaced elements
• filter for element type, content type and element difficulty

[coveralls]

Pull Request Test Coverage Report for Build 8097902382

Details

• 8 of 109 (7.34%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.4%) to 79.786%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
AuthoringTool/Startup.cs	0	2	0.0%
Shared/LearningElementDifficultyHelper.cs	0	10	0.0%
Presentation/Components/Forms/Element/UnplacedElementsDropZone.razor	8	97	8.25%
<!--	Total:	8	109	7.34%	-->

Totals
Change from base Build 8097402303:	-0.4%
Covered Lines:	14892
Relevant Lines:	18665

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💛 - Coveralls