zstd: vendor python-zstandard 0.8.0 Commit 81e1f5bbf1fc54808649562d3ed829730765c540 from https://github.com/indygreg/python-zstandard is imported without modifications (other than removing unwanted files). Updates relevant to Mercurial include: * Support for multi-threaded compression (we can use this for bundle and wire protocol compression). * APIs for batch compression and decompression operations using multiple threads and optimal memory allocation mechanism. (Can be useful for revlog perf improvements.) * A ``BufferWithSegments`` type that models a single memory buffer containing N discrete items of known lengths. This type can be used for very efficient 0-copy data operations. # no-check-commit

--- a/contrib/python-zstandard/c-ext/frameparams.c	Sat Apr 01 13:43:52 2017 -0700
+++ b/contrib/python-zstandard/c-ext/frameparams.c	Sat Apr 01 15:24:03 2017 -0700
@@ -127,6 +127,6 @@
 		return;
 	}
 
-	Py_IncRef((PyObject*)&FrameParametersType);
+	Py_INCREF(&FrameParametersType);
 	PyModule_AddObject(mod, "FrameParameters", (PyObject*)&FrameParametersType);
 }