Sorry for the fact that there are overlapping three commits in here...

1.  Make -fno-monomorphism-restriction 
    and -fno-implicit-prelude reversible, like other flags

2.  Fix a wibble in the new ImportAvails story, in RnNames.mkExportAvails

3.  Fix a Template Haskell bug that meant that top-level names created
    with newName were not made properly unique.