#42 OBJ material emissive/group name fixes

[sebj]

Two fixes for the OBJ importer:

1. Support for the emissive material property ("Ke")
2. In the getMaterialDesc() function, the current object is set to null if it is already initialised (has geometric data) (because the same mesh cannot have two materials applied, it must be split), prompting a new object to be created in getFace(). However, the new object always takes the name "defaultobject". The result is if multiple meshes have the same name, or rely on the name cascading, one or more will be renamed. This fix preserves the intended names by checking for, and utilising, the name of the last encountered object when creating a new one in getFace().

[sebj]

Patch file