Updated TODO
Disable 'path'
Add TODO
Conditional axis generation
Slightly more tolerant parsing of null values

These can result when using YAML as input
Use index types instead of enumerating aesthetics
Make 'point' an alias for 'symbol'
Check off an item
When missing a Cartesian dimension, center the chart
Grid lines for continuous axes
Give areas a default x2/y2
Fix commented legend code
Default fill for rect/bar
Make `line` ignore fill, add `polygon` which is filled
Get rid of centering, it's problematic
WIP