Layer Improvements

[eveninglily]

Implement the layers system again.

This includes

Saving/Clearing individual layers Hiding/showing layers Merging Per layer opacity Rearrange layers? Could require rewrite of parts of it Preview of layer in layers window

[eveninglily]

Layer system works of https://github.com/McIntireEvan/drawingapp/commit/0b19645622189f75d8018c381a3fe6edad338a0d

Next up is to add the hide/show feature again. Just simple .hide() and .show() and image replacing

After that, merging. All the code exists, it just needs to be put together in the correct way to achieve the desired effect

Renaming layers is simple and just requires some jquery and front-facing stuff, the names are not important to the code

Rearranging layers should be possible and probably requires just swapping the contents/properties of the layers

[eveninglily]

37 #39 are also related

[eveninglily]

https://github.com/McIntireEvan/drawingapp/commit/cee7e3a92d76d8a59f08879dce43f5ecd6401fdf adds renaming. Current todolist (in order) looks like

Layers Renaming Visibility Merging Opacity Reordering

[eveninglily]

https://github.com/McIntireEvan/drawingapp/commit/bfb94420e77bea17dfe60c8e8b6c706626799a7e and https://github.com/McIntireEvan/drawingapp/commit/2757d54f2f73603aaccfc389eedbd476e6a1dbbd

leave only reordering and saving all the layer info left. Closing those tickets (#37 #39)and referring here instead