Support msgpack-1.0.0 (packing part)

The default value of the 'use_bin_type' option was changed in
msgpack-1.0.0. We should support different versions of the library and
provide the same behaviour across them.

Aside of this, 'encoding' option was dropped since this version of the
msgpack library, but we didn't actually support it for packing.  Binary
strings are packed as is, Unicode strings are encoded as UTF-8 and
nothing is changed regarding this.

Fixes #155

Author: Totktonada

tarantool/request.py

@@ -65,7 +65,19 @@ def __init__(self, conn):
         self._sync = None
         self._body = ''
 
-        self.packer = msgpack.Packer()
+        packer_kwargs = dict()
+
+        # use_bin_type=True is default since msgpack-1.0.0.
+        #
+        # The option controls whether to pack binary (non-unicode)
+        # string values as mp_bin or as mp_str.
+        #
+        # The default behaviour of the connector is to pack both
+        # bytes and Unicode strings as mp_str.
+        if msgpack.version >= (1, 0, 0):
+            packer_kwargs['use_bin_type'] = False
+
+        self.packer = msgpack.Packer(**packer_kwargs)
 
     def _dumps(self, src):
         return self.packer.pack(src)