Revamp pylintrc

- use the [MAIN] category instead of [MASTER]
- fix "Unrecognized option found: max-branchs"
- drop bad-functions option: "Unrecognized option found: bad-functions",
  this one can be enabed explicitly, but we don't seem to need it:
  'load-plugins = pylint.extensions.bad_builtin'

mock/pylintrc

@@ -1,6 +1,6 @@
 # mock pylint configuration
 
-[MASTER]
+[MAIN]
 
 # Pickle collected data for later comparisons.
 persistent=no
@@ -96,9 +96,6 @@ good-names=i,j,k,ex,Run,_
 # Bad variable names which should always be refused, separated by a comma
 bad-names=foo,bar,baz,toto,tutu,tata
 
-# List of builtins function names that should not be used, separated by a comma
-bad-functions=apply,input
-
 
 [DESIGN]
 
@@ -112,7 +109,7 @@ max-locals=20
 max-returns=6
 
 # Maximum number of branch for function / method body
-max-branchs=20
+max-branches=20
 
 # Maximum number of statements in function / method body
 max-statements=50
@@ -130,9 +127,6 @@ min-public-methods=1
 max-public-methods=20
 
 
-[CLASSES]
-
-
 [FORMAT]
 
 # Maximum number of characters on a single line.