Texture conflict when using textures with the same name but from different locations

*ArmorLab 0.1-7bc8676, Windows*

**Issue description:**
When I import a new texture with the same name as another one (but with a different filepath) ArmorLab uses the other texture instead of the one I just imported.

**Steps to reproduce:**
- Import a texture.
- Import another texture with the exact same name but from a different location.

Start by reproducing the issue in ArmorLab on Windows: import one texture, then another with the same name from a different filepath. Trace the texture import and lookup path to determine where the collision occurs. Done means both imported textures remain distinct and the second import is used correctly.

Written by the indexing model from the issue text.