split Cython's Generator type into separate Coroutine and Generator types to prepare PEP 492 implementation

avoid runtime 'in' tests for dict literals when we can determine at compile time that there are no duplicate keys

mofe GIVEREF() before PyTuple_SET_ITEM() call because that's when we still own the reference (pypy needs it that way)

mofe GIVEREF() before PyTuple_SET_ITEM() call because that's when we still own the reference (pypy needs it that way)

switch to using PySet_GET_SIZE() for set size and truth requests as it's fast and also works as expected in PyPy

optimise kwargs dict creation away when it's only being passed on and not otherwise modified (ticket 744)

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extra : transplant_source : %1D%D3w%5B%A2%3E%5D%E2S%F8%BB%BAql1%D3%E9%D9%22%83

Their temporaries can't be references.

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extra : transplant_source : %2CJ%21%D7%9F%FD%C0v%C8U%15%3B%B2%C7%23%BF%FC%A4%E8%13