fixed #67, and moved zero line styling to the css
fixes #75 one too many y-axis tick groups
Merge branch 'master' of https://github.com/Quartz/Chartbuilder
hid custom hex value input in picker by default
validation allows for nulls and blanks, fixes #76
fixed typo that prevented export
Merge branch 'master' of https://github.com/Quartz/Chartbuilder

Conflicts:
	js/gneisschart.js