Diagnose erroneous uses of out-of-line member definitions and scope

specifiers. Specifically: 
  * Determine when an out-of-line function definition does not match
    any declaration within the class or namespace (including coping
    with overloaded functions).
  * Complain about typedefs and parameters that have scope specifiers.
  * Complain about out-of-line declarations that aren't also
  definitions.
  * Complain about non-static data members being declared out-of-line.
  * Allow cv-qualifiers on out-of-line member function definitions.

llvm-svn: 61058