Now Native PhpStorm now bundles WordPress coding style natively, starting from version 8. Go to Project Settings > Code Style > PHP. Select Set From... (top right of window) > Predefined Style > WordPress. No longer need to muck with this import! :)
Recommended Books A list of useful books to improve your skills Recommendations from others are noted in (parentheses). The rest are my personal recommendations. Programming Building your core The Pragmatic Programmer - Hunt & Thomas