feature request: import material(s) from igm

[egornot]

for now using external material is more like notepat to blendigo copypaste. will be great do it with IMPORT button. oh, maybe even convert to blender matterial approximation with another button...

this also a bit about blendigo functionallity: will be great to manage materials not necessary exist in blender. for examle using external you can just type name with no blender same-name-material-creation.

thankx for you great work anyway,
chao.