AST Dump: print the Inherited flag on attributes

Also move the attribute-specific dumping to after dumping this and
the Implicit flag.

Differential Revision: http://reviews.llvm.org/D3971

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@209965 91177308-0d34-0410-b5e6-96231b3b80d8