Piskel missing good features

[raiguri]

External image editor

Edit: topics discussing different softwares to replace Piskel hed been merged with this one. Add feature to use external image editor. In the gdevelop editor preferences we choose path to software.exe, and then when we edit sprite in gdevelop, instead of “Edit with Piskel” button, we see “Edit with software.exe”, and when we press this button we open sprite with external editor. It will be just useful and faster, than seeking the needed file in folder structure and then loading it manually …