A very much needed update - 1.6.1

• Added a new package file format: .zpk "ZLE package" - allows sharing ZLE projects as a single file
• Files window now creates and uses low quality thumbnails of images instead of full quality - stored in Cache/Thumbnails - way faster loading
• Images in files window no longer stretched
• Zoom main view based on mouse position
• Added ZLE loader from 1.5.3 - 1.4.x and 1.5.x projects can now converted to 1.6.x
• New tilemap and particle system file formats (.tlm and .psy) - old formats are now deprecated
• Added touchpad support for moving main view
• Squared files can be opened from the files window
• Files can now be "shown" on Windows in File Explorer
• Slightly reworked right click in main view and added shortcuts
• Added popup when exporting images since exporting can take a while
• Added enable/disable particle system updating
• Updated to ImGui 1.91.6
• Switched to SFML 2.6.2
• Missing assets shouldn't cause issues anymore
• Scene assets now expand when selecting item
• Settings design slightly reworked
• Settings is now one button, other options have moved to "Other"
• Added a setting for auto applying shader uniforms
• Added the ZLE logo to the about menu
• Files now show image thumbnails by default
• Fixed tile X and tile Y UI being positive between -1 and 0, added one extra decimal point
• Fixed autocomplete bugs
• Fixed a layout saving/overwriting bug
• Removed particle systems in separate threads due to bugginess and not much use