Correct incoherent function versus function template partial ordering for conversion operators (the comparison could claim that two conversion operators are both better than each other). Actually implement DR495, rather than passing its test by chance because the declarations happened to be in the "lucky" order.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@209054 91177308-0d34-0410-b5e6-96231b3b80d8