When using `NUMBA_DISABLE_JIT=1` we still want `dictobject.new_dict` to
work, for example to measure coverage and such things.

* master: (252 commits)
  Use class name in the tuple type name
  Fix tuple type used for stararg
  Remove deadcode
  Fix test failure depending on pointer size
  Revert "Replace `arange` with `ones`"
  Revert "Fix arange type in list tests"
  Respond to feedback
  Add problematic case for tuple in stararg
  Attempt to fix numba#4944
  Implement sort/sorted with key.
  Clarify comments
  Use guarded function
  Apply suggestions from code review
  Undo "fix" to block-0 loop header because it is causing segfault in numba.tests.test_closure.TestObjmodeFallback.test_issue3239.
  Fixes a bug in the relabelling logic in literal_unroll.
  Set the calltype on the newly formed SetItem when we replace StaticSetItem with regular SetItem.
  Fix the extraction of code to common function gen_wrap_if_not_known.
  Clean up
  Update looplifting test that now improved in py2 because of the new loop-canonicalization pass
  Fix test error on windows
  ...

This implements most methods for creating typed-dicts with JIT disabled
and tests those.

When using `Dict()` with DISABLE_JIT we now return a `dict` which should
then survive any kind of mutation.