Systemd service for client autostart instead of xdg-autostart

[Jai-JAP]

Use a systemd service to launch the client on login instead of using the xdg-autostart .desktop file.

This will essentially serve the same purpose to autostart the client on user login but will have the systemd backend just as for keymapperd.

It allows us to properly control client's execution and triggering on a per user basis using systemctl instead of having to modify the .desktop and copying it to user's autostart directory.

This will have both the autostart tasks to only use systemd for handling, instead of them having different approaches.

The systemd service file for this would look like

[Unit]
Description=Keymapper Client

[Service]
ExecCondition=systemctl is-active keymapperd.service
ExecStart=keymapper

[Install]
WantedBy=default.target

Important to note that this unit file needs to be placed in /lib/systemd/user/keymapper.service in order to make it as a user unit.