FEATURE | Merged tile support

[phobos2077]

I like to combine tiles for one region (like a set of islands) together in one folder. This avoids some duplicated files and allows for cleaner file structure (e.g. easier to disable/delete regions I don't want without looking up all the tiles coordinates involved). But now if I do that, these tiles disappear from the "Tiles collection and management" window and I lose the ability to update them.

Would be great to add logic that will:

• Scan all folders in Base Folder starting with zOrtho4XP, not just those with tile coordinates, like "zOrtho4XP_Bahamas".
• If multiple cfg and other Ortho4XP-related files are found, load all of them from that folder (as separate tiles).
• Show these tiles normally in "Tiles collection and management" window.
• When processing (manually or in batch mode), use the folder where the tile was found to read/write data to.