[Suggestion] make offline version installation more convenient on Linux

[pythonian23]

I composed two .sh files for easy installment and uninstallment of Piskel, along with a .desktop file for easy access. If these were included in the linux download, installing Piskel would be much more convenient.

install.sh

sudo cp -r ./ /usr/share/piskel/
cd /usr/share/piskel

sudo ln -s /usr/share/piskel/piskel /usr/bin/piskel
sudo wget https://www.piskelapp.com/static/resources/favicon.png && sudo ln -s /usr/share/piskel/favicon.png /usr/share/icons/piskel.png
sudo cp /usr/share/piskel/piskel.desktop /usr/share/applications/piskel.desktop

uninstall.sh

sudo rm /usr/bin/piskel
sudo rm /usr/share/icons/piskel.png
sudo rm /usr/share/applications/piskel.desktop

sudo cd ~/
sudo rm /usr/share/piskel/ -r

piskel.desktop

sudo rm /usr/bin/piskel
sudo rm /usr/share/icons/piskel.png
sudo rm /usr/share/applications/piskel.desktop

sudo cd ~/
sudo rm /usr/share/piskel/ -r

[pythonian23]

zip file with changes included