Error messages when using safevarargs annotation incorrectly

[Markus Olsson]

ExtendJ 8.0.1-196-gc01b244 JavaSE 8

The error message when using safevarargs annotations incorrectly is not very informative and sometimes incorrect. The error message is "@SafeVarargs is only allowed for variable arity method and constructor declarations". This is incorrect if the method is a variable arity method that is not static or final.

[Jesper Öqvist]

More precise @SafeVarargs misuse errors

This adds more precise error messages when the @SafeVarargs annotation is used incorrectly.

fixes #215

→ <<cset a9ab455c301d>>