Move Javascript out of PHP files

Working on it

aaron.ferris → made their first commit to this issue’s fork.

Made a start on this, it's functional to the point of working the same as the old behaviour, just from libraries/preprocess. Ive removed all the JS building code.

We need to test this further with how flexible it can be in adding new widgets, as the hook to build the widgets is gone.

nexusnovaz → changed the visibility of the branch 3511227-move-javascript-out to hidden.

Code looks good to me and functions as expected