Create docs Folder
Create a folder for holding documents.
Support PE Waste on Extra Materials
This changes add support for PE waste on extra materials. If a material
is listed in both regular materials and extra materials, regular materials
have ME and PE waste applied; extra materials just have PE waste applied.

This also fixes a problem where extra materials were overriding regular
materials. To accomplish this, the perfectMaterials object in the return
value changes to an array. The objects in this array are materials that
have a material ID.