utils: pep8 fixes

wa/utils/exec_control.py

@@ -31,6 +31,7 @@ def activate_environment(name):
         init_environment(name)
     __active_environment = name
 
+
 def init_environment(name):
     """
     Create a new environment called ``name``, but do not set it as the
@@ -44,6 +45,7 @@ def init_environment(name):
         raise ValueError(msg)
     __environments[name] = []
 
+
 def reset_environment(name=None):
     """
     Reset method call tracking for environment ``name``. If ``name`` is
@@ -63,6 +65,7 @@ def reset_environment(name=None):
             activate_environment('default')
         __environments[__active_environment] = []
 
+
 # The decorators:
 def once_per_instance(method):
     """
@@ -81,6 +84,7 @@ def once_per_instance(method):
 
     return wrapper
 
+
 def once_per_class(method):
     """
     The specified method will be invoked only once for all instances
@@ -100,6 +104,7 @@ def once_per_class(method):
 
     return wrapper
 
+
 def once(method):
     """
     The specified method will be invoked only once within the