Upgrade to pylint 1.4

* New version supports only Python 2.7+, ships more checkers, can run
  checks in parallel and warns about constructs invalid in Python 3.
Update pylint configuration file.

* Only allow C extensions of pysqlcipher to be loaded automatically.
Suppress errors from new checkers.
Remove version constraint on astroid.

* New pylintrc allows loading of C extensions.
Merge pull request #1084 from Renelvon/pylint1.4

Upgrade to Pylint1.4