Fix #671: Add corejslib to html files using packaged JS
Merge pull request #683 from gzm0/fix-package

Fix #671: Add corejslib to html files using packaged JS
Fix #682: Use new source map syntax
Fix #681: Make js.Dictionary.delete return Unit

Consequently, the JSDelete tree becomes a statement.
Merge pull request #686 from gzm0/various-fixes

Fix #682: Use new source map syntax
Merge pull request #687 from gzm0/unit-delete

Fix #681: Make js.Dictionary.delete return Unit
Fix #685: Create dummy parents in fastOptJS
Merge pull request #689 from gzm0/fastopt-dummy-parents

Fix #685: Create dummy parents in fastOptJS
wip