radius

• threshold: replace "Window Size" to "Radius"
• threshold: refactoring GatosCleaner
• threshold: add lower/upper bounds
• margins: modify RelativeMargins for base size
• filters: fix Screen
• filters: add Equalize

Build for Windows; flatpak by @plzombie .
Build for Mac by @gasparschott .
Build for Debian GNU/Linux by @zvezdochiot .