Reintroduce Magma Block Light Storage

When they were first introduced, magma blocks had the ability to store light and emit said light value. This bug also effect other blocks, but magma blocks were where it was most notable, as they had a much lower light level. I think that this "bug" would make a great feature, just simply store the light value as blockdata, and emit a light of that brightness. By default the value would be 3, but could be any number 0-15 via commands. This would allow map makers to better tune the lighting of their maps, and could allow some interesting datapack/command creations. As for how the player would use it, the magma block would check for lighting updates, and when there is a lighting update, it would store what the light value should be at it's position. If it is higher than what it currently is, then it would store it as it's new light value, otherwise it would ignore it. Breaking the block and placing it back would reset the light level back to the default value. A way to reset the value without breaking the block might also be useful, but there doesn't seem to be a good way to do so that I can think of.