suggestion: remove texture dialog

[kfarr]

Texture modal dialog is the cause of many issues on github:
#429
#471
#494
#508
#621

it also appears to re-download textures when i look at network activity, effectively doubling download bytes.

Would it make sense to remove this feature?

[vincentfretin]

If the direction that @dmarcos want this repo to take is to stay an inspector and not add any new features to be more an editor, it would make sense to drop this feature indeed, and also remove the aframe-watcher button #679
We can implement a better editor in a fork, I started one in https://github.com/c-frame/aframe-editor to add drag an drop, but no specific roadmap for now.