SYL - new phase

Hi there
Some news:

New version for this sunday!

• I change api and language. I switch to C# and FNA. For me it's easier to maintain c# code than lua
• I try to make better wall. Not an easy task for me.
• I implement a first step of progressivity. You start with one or two monsters and finish with plenty of them.
• At the moment the goal stay the same: make a maximum score and to do a maximum score you have to take gems, kill monsters and go down. Later a little story and a heroic goal will be added (save a  princess)
• Shield and bow are added
• First floor trap added
• Monsters have different attacks (jump, weapon, ...)