Add N-dimension array class
Merge pull request #1 from ecomfe/master

代码规范
Merge branch 'master' of https://github.com/pissang/echarts
add chord chart, improve ndarray
Merge https://github.com/ecomfe/echarts/commit/fadd309b34384bf643ab0c65bcc50c45201686df
Add hover highlight, fix scale compute
fix line
Merge pull request #94 from pissang/master

添加Chord，多维数组处理类ndarray