Description of problem:
When user enter WebTrans, if server is down or connection is lost, client is still not notified by this. When then perform an action needs to call the server, they will get back an specific error but not knowing the root cause. In some occasion error may only get logged into console and hidden from user.

Version-Release number of selected component (if applicable):
2.0-

How reproducible:
Always

Steps to Reproduce:
1.Go to WebTrans translation editor
2.Shutdown server
3.Perform an action like selecting a translation unit, search in project or save a translation
  
Actual results:
An specific error will show, i.e. search failed, TM or glossary result not coming back but logs an error in browser console.

Expected results:
Client should be notified that the connection to server has lost and they should refresh their browser to make sure the connection is still live.

Additional info: