Allow code contributions under a CLA

[alranel]

I strongly advice to start accepting code contributions, because several people might be interested in helping you improve this useful application by writing actual code. If you still plan to release this application under different licenses, I suggest to integrate this repository with https://cla-assistant.io which allows to collect CLAs easily :)

[tumic0]

Thanks for the link, that could make a lot of things much easier. There is however still the problem of the content (text) of the CLA. I'm not a lawyer so creating such a text is quiet hard/annoying for me and till now it has not prevail the benefits of the contributions that anyone wanted to do (usually those are small pieces of code or even stuff that does not meet the standards/direction where i want GPXSee to go).

But let's let it open, maybe I will find some time to do something about it.

[sikmir]

Just in case, there is another option:

• EasyCLA (integration via GH app)