Added ReprapWorld Keypad Buttons Actions

F1: Emergency Stop
F2: Z up
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Revert "Added ReprapWorld Keypad Buttons Actions"

This reverts commit d4871e050df1f96c7cf56be4d86f7755f36a36ec.
Revert "Revert "Added ReprapWorld Keypad Buttons Actions""

This reverts commit 19772de696354c153d102d22b2eb8c60db4f8c94.