Warning fixes from Nelson

* merges:
  Remove casts which were not needed and causing comparison sign mismatch
  Add prototype for emacs_tparam to avoid warning
  Change the pre-processor conditional to check for MPC_SET_UI_FR to avoid warning
  Add new Assert-Equal and Assert-Not-Equal macros to test-harness, which print the actual values in case of failure. Use instead of (Assert (equal)) and (Assert (not (equal)))