Color management

[eolmapper]

Idea for improuvement: add a color association table when importing a file.

I often have this problem when I combine two pieces of map with different symbol sets or when I add symbols for a school map for example. OOM adds the new ones colors if they are not 100% identical to the existing ones (some time, only the name is différent). So we have a table with lots of colors that are not always in the right place and it's a mess.
My proposal is to have an association table for the colors which will look like the symbol association table. On one side the imported colors and on the other a drop-down menu with the existing colors by which we can replace them or choose to add this color at the top of the table or at the bottom of the table.