TUNE Delay Switch, Issue #558

- Add a -DELAY switch to the TUNE command line to force the use of delay mode for note pacing.  Issue #558  Credit to @robbbates for suggesting this.
- Add missing include file logic for DS1307, Issue #556.  Credit to @tpycio.
- Miscellaneous documentation improvements per Peter Onion and Petr Antos.

Doc/ChangeLog.txt

@@ -5,6 +5,7 @@ Version 3.6
 - WBW: Enabled dynamic CPU speed update on LCD screen
 - WBW: Improve LPT driver boot messaging when not detected (per Robb Bates)
 - WBW: Correct DS1307 boot date/time display (per Tadeusz Pycio)
+- WBW: Add -DELAY option to TUNE app (per Robb Bates)
 
 Version 3.5.1
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