Support Serf v0.7.0, closes #28

Serf v0.7 was released on Dec 21, 2015 as part of `0df3e3df1` at
https://github.com/hashicorp/serf

This change means we support the latest release of Serf.

Author: KushalP

.travis.yml

@@ -8,8 +8,8 @@ python:
   - "2.7"
   - "2.6"
 before_install:
-  - wget https://releases.hashicorp.com/serf/0.6.4/serf_0.6.4_linux_amd64.zip
-  - unzip serf_0.6.4_linux_amd64.zip
+  - wget https://releases.hashicorp.com/serf/0.7.0/serf_0.7.0_linux_amd64.zip
+  - unzip serf_0.7.0_linux_amd64.zip
   - ./serf agent &
   - sleep 1 ; ./serf tags -set foo=bar
 install:

tests/test_client.py

@@ -44,22 +44,26 @@ def test_force_leaving_of_a_node(self, serf):
             {b'Error': b'', b'Seq': 1}
 
     def test_joining_a_non_existent_node(self, serf):
-        join = serf.join(['127.0.0.1:23000'])
+        address = '127.0.0.1:23000'
+        join = serf.join([address])
         assert join.head == \
-            {b'Error': b'dial tcp 127.0.0.1:23000: connection refused',
-             b'Seq': 1}
+            {
+                b'Error': 'dial tcp {addr}: getsockopt: {reason}'.format(
+                    addr=address,
+                    reason='connection refused'
+                ).encode('utf-8'),
+                b'Seq': 1
+            }
         assert join.body == {b'Num': 0}
 
     def test_joining_an_existing_node_fails(self, serf):
         join = serf.join(['127.0.0.1:7373'])
-        assert join.head == {b'Error': b'Reading remote state failed: EOF',
-                             b'Seq': 1}
+        assert join.head == {b'Error': b'EOF', b'Seq': 1}
         assert join.body == {b'Num': 0}
 
     def test_providing_a_single_value_should_put_it_inside_a_list(self, serf):
         join = serf.join('127.0.0.1:7373')
-        assert join.head == {b'Error': b'Reading remote state failed: EOF',
-                             b'Seq': 1}
+        assert join.head == {b'Error': b'EOF', b'Seq': 1}
         assert join.body == {b'Num': 0}
 
     def test_member_list_is_not_empty(self, serf):