Skin manager update!

• reworked skin displaying modes, added several ways to add skins to the launcher including uploading a skin, browsing existing skins or choosing a default skins, creating a new skin with the simple or advanced skin editors, or wrap a regular image to a minecraft skin
• fixed several issues including the launcher not working properly when there is no theme set, filtering issues
• new developer mode - when it isnt enabled now the devtools menu isnt openable, and enabling it also adds a feature called devmods, which allow to specify a build directory for a mod, and when a new version of the mod is built the version in the launcher is instantly updated
• the launcher now doesnt freeze when an instance is launching and when launched from a desktop shortcut now there is a progress bar window showing.
• other minor changes and stability fixes