[Checkers] Questions about Javari quals

[Telmo]

> 1. Should PolyRead accept a String[] value?  If so, what does it mean and can 
> you document it?

I don't think PolyRead accepts a String[] value. There was a discussion at 
some point about passing parameters to it, but the Javari seems expressive 
enough without it.

> 2. What does @Unmodifiable mean?  I see no use of it in the checker itself. 
> I've heard that at some point it was for immutable classes, but it seems that 
> ReadOnly does that now too.  Should we delete it?

Yes. @Unmodifiable used to mean @ReadOnly for classes only, on some old 
annotation repository, but it is not part of the Javari language. Any use 
of it should be replaced with @ReadOnly, and the annotation can be 
removed.