Separate package for image manipulation

[johanlef]

Create a new LEF package to manipulate images:

• [ ] rotate
• [ ] crop
• [ ] color conversion (color, black and white)
• [ ] adjustments (brightness, saturation, …)
• [ ] water mark with another image

This must be available as a layer before uploading. (e.g.: an edit button next to the local preview)

We want to do this client side because most modern browsers run on machines with enough processing power to achieve this.

Note: the imgupload package already includes a resize option which uploads several smaller images from the same original.

[johanlef]

react-image-crop could be helpful here.