Initilize object options with "NONE", so the corresponding entry
in objectOptions_ is created, avoiding a past-the-end access later.

Crash backtrace:
```
  * frame #0: 0x0000000149a63f7c libPlugin-FileOBJ.so`OBJImporter::isCurve(this=0x00000001772de0b0, _objectID=0) at OBJImporter.cc:794:10
    frame #1: 0x0000000149a184b0 libPlugin-FileOBJ.so`FileOBJPlugin::checkTypes(this=0x0000000105583380, _bufferedFile=0x00000001772de028, _filename=QString @ 0x00000001772ddfe8, _importer=0x00000001772de0b0, _includes=0x00000001772de098) at FileOBJ.cc:1768:25
    frame #2: 0x0000000149a19124 libPlugin-FileOBJ.so`FileOBJPlugin::loadObject(this=0x0000000105583380, _filename=QString @ 0x00000001772de3b0) at FileOBJ.cc:1866:3
```