Charts - Fixes to ensure candlestick series renders as nicely as possible.

Proposed fix: for https://github.com/yui/yui3/issues/1393

Update candlestick series to allow for a specified spacing and size the candles based by the spacing when available and ensuring that wicks are centered and all parts are drawn on the pixel to avoid blurring.


Need to test:
- [ ] ie6
- [ ] ie7
- [ ] ie8
- [ ] ie9
- [ ] ie10
- [ ] ie11
- [ ] mac safari
- [ ] ios safari
- [ ] android 2.3.4
- [ ] android 4.1.1
- [ ] firefox
- [ ] chrome