1. Must be initialized in-place
2. Can not be open/abstract
3. Can not be an override
4. Can not be delegated
5. Initializer must be a compile-time constant
6. No getters
7. `const` is not applicable to vars or locals
8. `const val` should be whether top-level property or object member
But still resolve them as annotations.
Mostly it's needed as begin of migration path, one day they become modifiers anyway
Some tests are dropped because they supposed that `annotation` should have parameter
Most of modifier diagnostic is expressed by REDUNDANT_MODIFIER, INCOMPATIBLE_MODIFIERS, REPEATED_MODIFIER, WRONG_MODIFIER_TARGET, WRONG_MODIFIER_PARENT.
A set of modifier diagnostics is not in use now (but not deleted yet).
Sometimes it's allowed to parse "annotation" unescaped even if other annotations must be escaped.
A set of annotations and their options tests.
A swarm of existing tests fixed (mostly kotlin.annotation.annotation() added to txt-files).
STUB_VERSION increased. Some quick fixes slightly changed.
Alexey Tsvetkov