TravisCI integration and updated test suite (#296)

* Make TravisCI setup

* Use pytest, move tests to seperate files

* Added system to check if `onX` events were successfully executed

tests/test_tests.py

@@ -0,0 +1,12 @@
+# -*- coding: utf-8 -*-
+
+from __future__ import unicode_literals
+
+import pytest
+
+
+def test_catch_event(client2, catch_event):
+    mid = "test"
+    with catch_event("onMessage") as x:
+        client2.onMessage(mid=mid)
+    assert x.res['mid'] == mid