fixed #54: add new wOBA/BIP, BABIP and BIP rate zone charts

As promised, a pull request for @kruser to review -- pending karma tests on the new functions. I went with 0.400 for both wOBA/BIP and BABIP, and 0.500 for BIP rate. Perhaps the red heat painting for BIP rate should be lower. I'll leave that up to @kruser's discretion. Later, I may take a look at BIP/Swing and HR/BIP or HR/FB or HR/non-GB (not sure what you'd call the latter).