feature/shared file systems: show share details (#127)

* sfs/shares: get a share with details

* sfs/shares: use AssertDeepEquals in get share test
diff --git a/openstack/sharedfilesystems/v2/shares/urls.go b/openstack/sharedfilesystems/v2/shares/urls.go
index 7cb1c81..309f071 100644
--- a/openstack/sharedfilesystems/v2/shares/urls.go
+++ b/openstack/sharedfilesystems/v2/shares/urls.go
@@ -9,3 +9,7 @@
 func deleteURL(c *gophercloud.ServiceClient, id string) string {
 	return c.ServiceURL("shares", id)
 }
+
+func getURL(c *gophercloud.ServiceClient, id string) string {
+	return c.ServiceURL("shares", id)
+}