JS backend minor: added @NotNull annotation to getArguments()
KT-4773: added tests
KT-4773: use receiver for delegated extension property
KT-5673: added tests
KT-5673: always write val property to backing field
More changes after replacing config directory

 - Plugin auto-enable script updated
 - Don't drop configured folder in update-dependencies
 - Drop test config and system folders in update-dependencies
Fix wrong containingDeclaration for property type parameter.
Fix variance problems.
Fix variance problem in quick fix test.
Added DiagnosticFactoryToRendererMap.put(Renderers.MultiRenderer)
Create AbstractDiagnosticWithParametersRenderer with renderParameters method.
Add support for check diagnostic parameters in test.
Added @NotNull
Add TypeBinding.
Create VarianceChecker.
Added VarianceChecker to TopDownAnalyzer.
Added Variance tests
Add variance check for class supertypes.