Added the cProfile module.

Based on lsprof (patch #1212837) by Brett Rosen and Ted Czotter.
With further editing by Michael Hudson and myself.
History in svn repo: http://codespeak.net/svn/user/arigo/hack/misc/lsprof

* Module/_lsprof.c is the internal C module, Lib/cProfile.py a wrapper.
* pstats.py updated to display cProfile's caller/callee timings if available.
* setup.py and NEWS updated.
* documentation updates in the profiler section:
   - explain the differences between the three profilers that we have now
   - profile and cProfile can use a unified documentation, like (c)Pickle
   - mention that hotshot is "for specialized usage" now
   - removed references to the "old profiler" that no longer exists
* test updates:
   - extended test_profile to cover delicate cases like recursion
   - added tests for the caller/callee displays
   - added test_cProfile, performing the same tests for cProfile
* TO-DO:
   - cProfile gives a nicer name to built-in, particularly built-in methods,
     which could be backported to profile.
   - not tested on Windows recently!

Modules/rotatingtree.h

@@ -0,0 +1,27 @@
+/* "Rotating trees" (Armin Rigo)
+ *
+ * Google "splay trees" for the general idea.
+ *
+ * It's a dict-like data structure that works best when accesses are not
+ * random, but follow a strong pattern.  The one implemented here is for
+ * accesses patterns where the same small set of keys is looked up over
+ * and over again, and this set of keys evolves slowly over time.
+ */
+
+#include <stdlib.h>
+
+#define EMPTY_ROTATING_TREE       ((rotating_node_t *)NULL)
+
+typedef struct rotating_node_s rotating_node_t;
+typedef int (*rotating_tree_enum_fn) (rotating_node_t *node, void *arg);
+
+struct rotating_node_s {
+	void *key;
+	rotating_node_t *left;
+	rotating_node_t *right;
+};
+
+void RotatingTree_Add(rotating_node_t **root, rotating_node_t *node);
+rotating_node_t* RotatingTree_Get(rotating_node_t **root, void *key);
+int RotatingTree_Enum(rotating_node_t *root, rotating_tree_enum_fn enumfn,
+		      void *arg);