The Particle system update - 1.4.0

What changed?

• Particle systems have additional 2 tabs: events & random
• Particle system events can be used in the level editor - which allows for chaining particle systems. Example: fireworks
• The random tab allows for more randomization of the effect.
• Added window docking - finally :)
• Added tooltips all over the place
• Added antialiasing setting
• Added BG color option
• Like last time, many behind-the-scenes changes in code to allow ex. Linux support in the future
• Added examples for tilemaps, particle systems, and the whole level
• Selecting an asset now always has 1-pixel thickness
• Removed the ability to set window resolutions lower than 800x600