Add high-frequency spindle output option. Minor parking motion re-factoring.

- Some laser controllers were reported to need a very high PWM
frequency. Added a line to enable this in cpu_map.h, if needed.

- Cleaned up some of the parking code. Mostly just editing the comments.

- Moved the accessory state resetting after the initial parking
retract. Should ensure the accessory state is properly handled upon an
aborted parking restore. Not certain if this was a problem before
though. Just to be sure.

doc/log/commit_log_v1.1.txt

@@ -1,3 +1,16 @@
+----------------
+Date: 2016-10-25
+Author: chamnit
+Subject: Mandate all probe cycles ignore feed overrides.
+
+- For repeatability reasons, all G38.x probe cycles ignore feed rate
+overrides and move at their programmed speed.
+
+- The mandate can be removed with a new config.h option.
+
+- Updated the documentation to reflect the change.
+
+
 ----------------
 Date: 2016-10-25
 Author: chamnit