Write more Unit Tests

[azeem]

We have lots of func tests here: https://github.com/azeem/webvs/tree/master/test/func that tests Components end to end inside a browser. This has been very useful when doing large refactoring/porting. However, it'd be nice if we have more unit tests for atleast the core parts:

• Component.ts
• ComponentRegistry.ts
• Container.ts
• EffectList.ts
• Model.ts
• Main.ts
• ResourceManager.ts
• webl/Buffer.ts
• webgl/ShaderProgram.ts
• webgl/TextureSetManager.ts

Use https://github.com/azeem/webvs/blob/master/test/unit/trans/DynamicMovement.test.ts as a reference for mocking and setup for unit tests.