Remove deprecated styler plugins and related components

[allyoucanmap]

Description

Currently we have two plugins Styler, RasterStyler and VectorStyler not imported in the MapStore product configuration. We could remove those styler to avoid duplication because the new visual style editor covers the same functionality. We should also remove all the dependant components and merge together the component/styleeditor with the component/style directory.

What kind of improvement you want to add? (check one with "x", remove the others)

• Other... Please describe: Remove deprecated code

Other useful information

[tdipisa]

@allyoucanmap as we discussed and reviewed together with @offtherailz, I think we can remove this deprecated code to clean up the MS codebase.