Symbol Raster Presets (maybe for all displays/plugins?)

[hello-adam]

It might be nice to have some preloaded Symbol Raster configurations. In theory this could be done for any plugin by just saving some preset parameter JSON, so maybe it should be pretty generic. It might even be just as easy to make a generic solution for all plugins (or at least all displays).

[hello-adam]

this might require making the symbol mapping parameter more expressive so that symbol ranges and masks can be used instead of 1-to-1 symbol-to-color mappings.