Implement more feedback:

Implement more feedback:
* Allow attributes to be added and removed singly or jointly so that in
  the future something like -pruneh can manipulate them more easily.
* Move functions generally only useful for LLVM internals to the end of
  the accessors list instead of the beginning.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35780 91177308-0d34-0410-b5e6-96231b3b80d8