Workaround: #37 - Added base pathing in static js

[lc787]

Workaround for #37
Okay, so the static files edit.js and utils.js don't really have a mechanism for relative path referencing. I've patched the scripts so it should be fine now. Unfortunately, I couldn't find a way to not hard-code netbox_root, but at least I got it in one place only so the workaround isn't hard to apply. Mind you, I'm not a frontend developer, so I don't know how feasible it is to do this without a build process.

[lc787]

There are a couple of hrefs that still don't work. The buttons 'Edit Floorplan' and 'Add Floorplan' under {netbox_root}/dcim/sites/{id}/floorplans/ for example. I'm not sure how the plugin framework works in netbox so I've yet to take a crack at it.

[ziggekatten]

I can get everything to work by also hacking the floorplan_view.html template, so now we can create floorplans, add racks, export SVG etc.

One thing does not work. Klicking on an rack in an floorplan does not include the NETBOX_ROOT, thsu giving an 404. My Javascript knowledge is limited, and this is far down in fabric-js generated stuff, so if anyone knows where I need to hack things to get this working i would be very happy