Refactor abilities. Added ProjectUpdate context. Fixed few bugs with namespaces

spec/models/group_spec.rb

@@ -24,7 +24,7 @@ describe Group do
   it { should validate_presence_of :owner }
 
   describe :users do
-    it { group.users.should == [] }
+    it { group.users.should == [group.owner] }
   end
 
   describe :human_name do

spec/models/namespace_spec.rb

@@ -55,9 +55,10 @@ describe Namespace do
   describe :move_dir do
     before do
       @namespace = create :namespace
+      @namespace.stub(path_changed?: true)
     end
 
-    it "should raise error when called directly" do
+    it "should raise error when dirtory exists" do
       expect { @namespace.move_dir }.to raise_error("Already exists")
     end