Tutorial — SailSim Steam update #1360765

In this update i created a Tutorial for all newcomers based on user requests. Sometimes the simplest things elude me since i was under the impression that everyone knows how to sail :) The Tutorial covers basic controls so you can begin exploring and learn further. For newcomers, the Tutorial will appear during the first Challenge automatically and when passed will allow to continue into the Challenges. For those who already have SailSim, you shall find the Tutorial under the "Quick Guide" in the Main Menu (Left bottom corner). If you haven't passed the Tutorial yet, it will also be triggered during the very first challenge "Get Points". Hopefully this will make life easier for new sailors and clarifies few things for existing ones :)