Remove residual decls from reporting.h
Return an enum SyntaxTypeMatch from constraint type matching

Instead of printing out error msgs as we go, we now return a common
return code for a whole range of constraint type errors. This makes the
quality of the error messages slightly worse in the short-term, but
will improve later.
Merge pull request #365 from sigurdteigen/cleanup/syntax-type-match

Cleanup/syntax type match