Fix Removing Circles and Polygons

[AV-GregMayes]

Issue:

We have noticed that removing circles and polygons doesn't work as there's a mismatch on the property names.

For circles, the pushed object to this.circles currently contains the keys id and marker whereas it should be id and circle based on what the removeCircle method expects. I have changed it to push an object containing id and circle.

For polygons/polygones, the pushed object to this.polygones contains the keys id and polygon whereas the removePolygone method expects the property on the object to be called polygones. I have changed removePolygone to expect polygon instead of polygones, as it's a singular context.

Breaking Changes:

This shouldn't introduce any breaking changes, as from what I can tell, these property names are only used when removing polygons and circles.

[AV-GregMayes]

Hi @dmandrade. Is it possible to have this pull request reviewed, please?

[dmandrade]

Thanks.