Django Admin Panel Improved

The django admin panel is now a little bit cleaner and easier to use. Apps and Checkboxes that nobody should use are removed (E.g. "isOscar API").
The Fullfillment Partner Page is now seperated into sections.

Now, it is much easier to understand that Panel.

Part Documents are optional again

That error message, that was annoying users who wanted to request a manual price, will not occur anymore

Performance Improvements

We optimized the loading times while loading the Materials and Services (both in the Drop-down and in the detailed listing). The time to load should now be ~double as fast.

x,y,z material values between 0 and 1

Now the minimums and maximums for the possible build area can be expressed in float numbers.

Improvements of new Service Panel

Quite a lot of improvements and small bug fixes where done here. (E.g. the comments are working now). The new Service Panel is as good as ready to go. Only the Texts need to be reviewed and translated.