upgrade style to sld 1.1

1. ✅ Deprecate (or just remove) the Style event notification code; it is broken unused and a bad idea

2. Upgrade GeoTools style classes to match SE 1.1 in place via a proposal

3. Rename org.opengis.sld to org.opengis.stlye and update with the interfaces matching GeoTools definitions (ie SE 1.1)

   • Go over SE 1.1 specification updating javadocs and methods as needed

4. Throw out GeoAPI org.opengis.feature.style package (it was working on graphic and is no longer needed)

5. Release a milestone GeoAPI jar

6. Change the GeoTools interfaces to extend the GeoAPI interfaces via a proposal (this is now possible with type narrowing!)