Use getTextRect to measure title size, also fix getTextRect so that any custom css font used is applied while measuring

Add the ability to prevent elements from the showing up in legend and tool-tip

Enforcing the AMD factory standard

Add chart.api ($$.api) to 'onunselected' callback

Patch for #1141

Update tooltip.js

Fix whitespace in README.md

Merge branch '1033_custom_legend_config' of https://github.com/davidpoore/c3 into davidpoore-1033_custom_legend_config