clipmenu: Fix systemd service, clipctl, clipmenud
clipmenu: Fix systemd service, clipctl, clipmenud

clipmenud.service:
- fix path to clipmenud

clipmenud:
- fix "ignore window" function by adding xdotools
- add coreutils to make clipmenud fully self contained (needed for
  systemd service)

clipctl:
- fix process name, caused by wrapping clipmenud

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