Create a supertype for all Kotlin annotations, jet.Annotation.
Map java.lang.annotation.Annotation to jet.Annotation and vice versa.
Add extension function "annotationType()" to every annotation, similar to java.lang.annotation.Annotation.annotationType()
#KT-1620 Fixed
Rename LazyClassDescriptor#onlyEnumEntries -> enumClassObjectInfo.
Determine ClassKind in JetClassInfo and JetObjectInfo constructor.
Remove complex constructor for enum entry in enum test.
Logic simplified in LazyClassMemberScope.
Minor refactorings.
In the most places in frontend identifier is stored in Name class, was in String.
Name has two advantages over String:
* validation: you cannot accidentally create identifier with dot, for example
* readability: if you see String, you don't now whether it is
identifier, fq name, jvm class name or something else
Name's disadvantage is (small) performance overhead. We have no value types in JVM.