add data scales, log10, srqt for starters

[lazarusA]

should this be done at the colormap, data or shader level ?

[TheJeran]

This is kind of #616

It should be done at the texture creation level. It can be done in shaders, but because the texture data comes in at Uint8, if you have a really big outlier: e.g; 254 and then the next highest value is like 180, you lose all of that information. At least I'm pretty certain that's an issue.

There is an option of allowing the users to do float16 textures and then we can do it directly in the shader. But that limits the amount of data that will fit on GPU.