Use laster version of the egg.

Tests do pass

https://nexedi.erp5.net/test_result_module/20180205-62704D70

(we can ignore git's hash in tests as I just rebased)

/reviewed-on !285

stack/erp5/buildout.cfg

@@ -730,7 +730,7 @@ spyne = 2.12.14
 suds = 0.4
 facebook-sdk = 2.0.0
 threadframe = 0.2
-timerserver = 2.0.2
+timerserver = 2.0.4
 urlnorm = 1.1.4
 uuid = 1.30
 validictory = 1.1.0