Added util function for getting signal names from signal numbers

cloudcontrol/node/utils.py

@@ -156,3 +156,11 @@ def set_signal_map(map_):
 
 sig_names = dict((k, v) for v, k in signal.__dict__.iteritems() if
                  v.startswith('SIG'))
+
+
+def num_to_sig(num):
+    """Returns signal name.
+
+    :param num: signal number
+    """
+    return sig_names.get(num, 'Unknown signal')