Add Custom LoadOrder

[Valen-H]

Is your feature request related to a problem? Please describe.
Loading of JS (and similar) files is non-deterministic currently, but we really need to know/control the order they'll get loaded because some files depend on other files. Currently you need to do dirty hacks to achieve this...

Describe the solution you'd like.
Perhaps sort the files alphabetically so we could prefix them with a number like 1_file.js, 2_script.js, etc...

Describe alternatives you've considered.
I considered using importScripts of SugarCube or altering the sources directory of tweego in the commandline but those both feel like fragile solutions...