various unicode fixes

Change-Id: Ia3a83b678a5084fd1d43b8cf513b296fdbde3d91
Reviewed-on: https://forge.frm2.tum.de/review/19198
Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>

secop_demo/test.py

@@ -20,6 +20,13 @@
 # *****************************************************************************
 """testing devices"""
 
+try:
+    # py2
+    unicode
+except NameError:
+    # py3
+    unicode = str  # pylint: disable=redefined-builtin
+
 import random
 
 from secop.modules import Readable, Drivable, Communicator, Parameter
@@ -89,4 +96,4 @@ class Temp(Drivable):
 class Lower(Communicator):
     """Communicator returning a lowercase version of the request"""
     def do_communicate(self, request):
-        return str(request).lower()
+        return unicode(request).lower()