Make v4 cache compatible with msgpack 1.0 in the future

The `encoding` parameter in `msgpack.loads` is deprecated and will be
removed in msgpack 1.0 [1].

Note that the `raw` parameter was called `raw_as_bytes` before 0.5.2
[2]. I add the version constraint to avoid API incompatibilities.

[1] msgpack/msgpack-python#191
[2] msgpack/msgpack-python@5569a4e

Author: yan12125

cachecontrol/serialize.py

@@ -181,7 +181,7 @@ def _loads_v3(self, request, data):
 
     def _loads_v4(self, request, data):
         try:
-            cached = msgpack.loads(data, encoding="utf-8")
+            cached = msgpack.loads(data, raw=False)
         except ValueError:
             return
 

setup.py

@@ -17,7 +17,7 @@
     include_package_data=True,
     description="httplib2 caching for requests",
     long_description=long_description,
-    install_requires=["requests", "msgpack"],
+    install_requires=["requests", "msgpack>=0.5.2"],
     extras_require={"filecache": ["lockfile>=0.9"], "redis": ["redis>=2.10.5"]},
     entry_points={"console_scripts": ["doesitcache = cachecontrol._cmd:main"]},
     python_requires=">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*",