Added skeleton window for smaple metrial dialog

Refs #10377
Populate a tree with basic data

Refs #10377
Better tree layout and algorithm buttons

Refs #10377
Added algorithm completion handler

Refs #10377
Change material name to formula

Refs #10377
Fix handling algorithm completion

Refs #10377
Do not allow duplicate observers on an algorithm

Add unit test for this

Refs #10377
Use std::find to search observers

Refs #10377
Revert "Use std::find to search observers"

This reverts commit c17b1dd1017433c17c6181f57d82235f49c2b239.

Refs #10377
Revert "Do not allow duplicate observers on an algorithm"

This reverts commit f6b01f277480cc07bff5ac71d500e7273588c53d.

Refs #10377
Do not clear the observer list

Refs #10377
Modify AlgorithmDialog to add observers just before execution

Refs #10377
Correct a documentation typo

Refs #10377
Merge remote-tracking branch 'origin/feature/10377_sample_material_ui'