add live preview 'sync error' status
remove lodash global
remove lodash script
fix unit test errors. rename event. fix error offsets.
remove _shouldClearErrors
use a line class instead of the line number gutter to show error status
fix position issues. fix error color per @larz0
use beforeChange event to remove line class before line handles change
update HTMLSimpleDOM tests to verify errors
Merge pull request #5151 from adobe/jasonsanjose/live-html-state

Add live preview 'sync error' status