show all courses/groups in browse mode, fixes #5674

Change-Id: Ie417757d4a5ed5f2d03d16984bcea1b14db8c279
Reviewed-on: https://gerrit.instructure.com/5747
Tested-by: Hudson <hudson@instructure.com>
Reviewed-by: Zach Pendleton <zachp@instructure.com>
Reviewed-by: Jacob Fugal <jacob@instructure.com>

app/coffeescripts/messages.coffee

@@ -1465,7 +1465,7 @@ I18n.scoped 'conversations', (I18n) ->
           if options.level > 0 then -1 else 5
         browser:
           data:
-            limit: -1
+            per_page: -1
             type: 'context'
 
     token_input = $('#recipients').data('token_input')

public/javascripts/compiled/messages.js

@@ -1989,7 +1989,7 @@
           },
           browser: {
             data: {
-              limit: -1,
+              per_page: -1,
               type: 'context'
             }
           }