IDEA plugin: added the error checking to intentions tests.
Minor: use canonical path to expected file in intention tests.
Fixed tests after adding error checking for intention tests.
Annotations on lazy classes are resolved lazily
Introduce JetModifierKeywordToken to mark keywords which can be used as modifiers

Change JetModifierList and JetModifierListOwner api to accept only those tokens
Make JetCompletionMultiTestBase extend JetFixtureCompletionBaseTestCase
Use common infrastructure for JetMultifileBasicCompletionTest
Switch JetMultifileBasicCompletionTest to generated approach
Script classes are public in LAZY mode
Account for script classes in getAllDescriptors()
Add 'rv' property to getAllDescriptors() in script classes
Properties from primary constructors added to getAllDescriptors()
In non-lazy mode, script classes are normal MutableClassDescriptors
Top-down analysis accounts for script classes too
Minor. Rename method BodiesResolveContext.getClasses()

This is done to avoid the clash of meanings with TopDownAnalysisContext.getAllClasses()
Unused mechanism removed

Incomplete traces are not needed for light classes any more, because light classes use lazy resolve
Added the directive for allow to use runtime classes in intention tests.
JS backend: - test both versions of Set(Complex and Primitive)

 - added size in PrimitiveSet
 - fixed contains in PrimitiveSet

 #KT-4796 fixed
JS backend: test both versions of Map(Complex and Primitive)