Feature local avatars and model images

I would like to get your opinion on the coding I have done for this as I feel there is better way to achieve the outcome but I am unable to think of it.

I understand that this is a non-important feature but thought I would give it a crack.

I am happy for this to stay as a PR if improvements can be made and also understand if it is not merged with the develop branch.

This also requires writable uploads folder in public with 2 sub folders avatars and models. It maybe possible to just have the sub folders writable.

Preview image
![mac-model-image](https://cloud.githubusercontent.com/assets/3274937/4821469/b505646e-5f2d-11e4-9954-b87c050e3734.png)