Add titles to all darkswarm pages

app/views/groups/index.html.haml

@@ -1,4 +1,7 @@
-= inject_enterprises 
+- content_for(:title) do
+  Groups
+
+= inject_enterprises
 
 :javascript
   angular.module('Darkswarm').value('groups', #{render partial: "json/groups", object: @groups})

app/views/groups/show.html.haml

@@ -1,3 +1,6 @@
+- content_for(:title) do
+  = @group.name
+
 -# inject all enterprises as "enterprises"
 -# it could be more efficient to inject only the enterprises that are related to the group
 = inject_enterprises

app/views/groups/signup.html.haml

@@ -1,3 +1,6 @@
+- content_for(:title) do
+  Sign up as a group
+
 #panes
   #shops-signup.pane
     .row.header