Add tooltips for master sync

Minor issue: 
"When tapped" German "Wenn angeschlagen, angetippt"
This sound for me as if the moment of the tab is relevant. Maybe I am wrong, but we use it in this meaning at the other occurrences in the tool-tips.
So what about just avoiding this possible misleadings and just use:
"Click to sync the tempo to other playing tracks or the master clock" (not sure about the colon before or)
"Hold for a second to ..