Normalize some URLs that used both .s and _s to use only .s

app/views/admin/LevelSessionsView.coffee

@@ -4,7 +4,7 @@ LevelSession = require 'models/LevelSession'
 CocoCollection = require 'collections/CocoCollection'
 
 class LevelSessionCollection extends CocoCollection
-  url: '/db/level_session/x/active?project=screenshot,levelName,creatorName'
+  url: '/db/level.session/x/active?project=screenshot,levelName,creatorName'
   model: LevelSession
 
 module.exports = class LevelSessionsView extends RootView

app/views/editor/campaign/CampaignLevelView.coffee

@@ -464,7 +464,7 @@ module.exports = class CampaignLevelView extends CocoView
       @analytics.recentSessions.data = data
       doneCallback()
     request = @supermodel.addRequestResource 'level_sessions_recent', {
-      url: "/db/level_session/-/recent"
+      url: "/db/level.session/-/recent"
       data: {slug: @levelSlug, limit: limit}
       method: 'POST'
       success: success

app/views/editor/level/systems/AddLevelSystemModal.coffee

@@ -5,7 +5,7 @@ LevelSystem = require 'models/LevelSystem'
 CocoCollection = require 'collections/CocoCollection'
 
 class LevelSystemSearchCollection extends CocoCollection
-  url: '/db/level_system'
+  url: '/db/level.system'
   model: LevelSystem
 
 module.exports = class AddLevelSystemModal extends ModalView