Tweaked custom PyLint configuration file.

.pylintrc-lib

@@ -189,7 +189,7 @@ allow-global-unused-variables=yes
 
 # List of strings which can identify a callback function by name. A callback
 # name must start or end with one of those strings.
-callbacks=cb_,_cb
+callbacks=cb_,_cb,cbk_,_cbk
 
 # A regular expression matching the name of dummy variables (i.e. expectedly
 # not used).
@@ -355,7 +355,7 @@ valid-metaclass-classmethod-first-arg=mcs
 [DESIGN]
 
 # Maximum number of arguments for function / method
-max-args=5
+max-args=6
 
 # Maximum number of attributes for a class (see R0902).
 max-attributes=7