Volumes are now prefixed with the project name

When created through the compose file, volumes are prefixed
with the name of the project they belong to + underscore,
similarly to how containers are currently handled.

Signed-off-by: Joffrey F <joffrey@docker.com>

tests/integration/volume_test.py

@@ -0,0 +1,55 @@
+from __future__ import unicode_literals
+
+from docker.errors import DockerException
+
+from .testcases import DockerClientTestCase
+from compose.volume import Volume
+
+
+class VolumeTest(DockerClientTestCase):
+    def setUp(self):
+        self.tmp_volumes = []
+
+    def tearDown(self):
+        for volume in self.tmp_volumes:
+            try:
+                self.client.remove_volume(volume.full_name)
+            except DockerException:
+                pass
+
+    def create_volume(self, name, driver=None, opts=None):
+        vol = Volume(
+            self.client, 'composetest', name, driver=driver, driver_opts=opts
+        )
+        self.tmp_volumes.append(vol)
+        return vol
+
+    def test_create_volume(self):
+        vol = self.create_volume('volume01')
+        vol.create()
+        info = self.client.inspect_volume(vol.full_name)
+        assert info['Name'] == vol.full_name
+
+    def test_recreate_existing_volume(self):
+        vol = self.create_volume('volume01')
+
+        vol.create()
+        info = self.client.inspect_volume(vol.full_name)
+        assert info['Name'] == vol.full_name
+
+        vol.create()
+        info = self.client.inspect_volume(vol.full_name)
+        assert info['Name'] == vol.full_name
+
+    def test_inspect_volume(self):
+        vol = self.create_volume('volume01')
+        vol.create()
+        info = vol.inspect()
+        assert info['Name'] == vol.full_name
+
+    def test_remove_volume(self):
+        vol = Volume(self.client, 'composetest', 'volume01')
+        vol.create()
+        vol.remove()
+        volumes = self.client.volumes()['Volumes']
+        assert len([v for v in volumes if v['Name'] == vol.full_name]) == 0