Remove dash from PieChart labels when label is empty (#26)

Co-authored-by: Jamie Schouten <[email protected]>

Add better defaults, add more color, font options. (#21)

Fix line not using x values correctly.
Reorder line point from y,x to x,y.

Area line (#19)

* Add area color to line

* Change all private to protected, remove readonly for easier extension

* Add better alt text

* Remove useless echo, fix chart rendering incorrectly the second time.

clean up svg content (#18)

Add better defaults (#17)

Add pdf example, add misc attributes (#16)

Add step line (#13)

Add curved line (#12)

Fix readme line breaks (#11)

Make Text readonly, Add pie chart (#9)

* make Text readonly

* Add Pie chart