Old system was hard to track in terms of usage and it's application of
'components' properties directly to elements was shoddy.
This routes usage via the components service, with element-specific
component usage tracked via a local weakmap.
Updated existing found usages to use the new system.
- Moved Code-editor from vue to component.
- Updated popup code so it background click only hides if the click
originated on the same background. Clicks within the popup will no
longer cause it to hide.
- Added session-level history tracking to code editor.
