First submission, and some thoughts

[Jummit]

I just found this project and love the idea of it! My first submission is a little fix to the particle trail: #121

As mentioned in other discussions, I think it would be good to put effort in organizing and streamlining the development and contributing process:

1. Documentation of the project structure: Where do which files go? How are scenes/scripts organized?
2. Automation of code review: Is the code formatted correctly, are variable/method names OK, is everything in the right place?
3. Writing a test process that one can follow to check if everything still works

None of these things are required, but would be nice to have.