"annotation" is now parsed as an identifier. It is no longer a soft keyword.

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.

compiler/testData/diagnostics/tests/enum/modifiersOnEnumEntry.kt

@@ -14,7 +14,7 @@ enum class E {
     <!ILLEGAL_MODIFIER!>final<!> FINAL,
 
     <!ILLEGAL_MODIFIER!>inner<!> INNER,
-    <!ILLEGAL_MODIFIER!>annotation<!> ANNOTATION,
+    <!ENUM_ENTRY_USES_DEPRECATED_OR_NO_DELIMITER!>annotation<!> ANNOTATION,
     <!ILLEGAL_MODIFIER!>enum<!> ENUM,
     <!ILLEGAL_MODIFIER!>out<!> OUT,
     <!ILLEGAL_MODIFIER!>in<!> IN,

compiler/testData/diagnostics/tests/enum/modifiersOnEnumEntry.txt

@@ -102,6 +102,16 @@ internal final enum class E : kotlin.Enum<E> {
         public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
     }
 
+    public enum entry annotation : E {
+        private constructor annotation()
+        public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: E): kotlin.Int
+        public final override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public final override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public final override /*1*/ /*fake_override*/ fun name(): kotlin.String
+        public final override /*1*/ /*fake_override*/ fun ordinal(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+
     public enum entry ANNOTATION : E {
         private constructor ANNOTATION()
         public final override /*1*/ /*fake_override*/ fun compareTo(/*0*/ other: E): kotlin.Int