Added offset files for XC pistes some ski areas in sweden.

[jetthe]

File names on the format "[Municipality][Ski area name]" to be able to distinguish between similar named ski areas and to find ski areas faster in offset lists. Perhaps "[Countrycode][Municipality]_[Ski area name]" would have been better? Or sub-directories for each [Countrycode]?

[yvecai]

Hello, nice work! I merge this, but I will take the opportunity to fix a few things before putting this live. You will have the chance to propose changes after that, but fro your information, here are the pitfall I try to avoid:

• Don't let gap between routes (A:1 / B:-1)
• Don't use offset >=3, or with great care.
• Don't use offsets on short overlapping length
• Avoid offsets on routes with sharp angles (otherwise this may create loops)
• Avoid offsets on complex loops (B-shape, for instance)
• Don't try to offset everything, if this doesn't work, this doesn't work that's all

These offsets are the closest thing to hand drawing the map I could find. However, this is still a blind algorithm that renders the map and if we don't pay attention, this can look really weird.

This is a good idea to add municipality name on the file name.

[yvecai]

The new offsets are now live, I took the time to expire tiles so you can directly have a look. There are some places where the route should be completed, though.