Add Jay Warrick to style checker's list of authors
DefaultOverlayService: add missing @Overrides
DefaultOverlayService: remove redundant javadoc

The javadoc is already declared in the interface. Recapitulating it in
the default implementation only invites the possibility of skew.
OverlayService: tweak javadoc
DefaultOverlayService: clean up style

Thank you, Eclipse code formatter.
DefaultOverlayService: fix method order

Public API should be in the same order it is declared in the interface.

And ImageJ code block ordering dictates that private helper methods come
before private helper classes; see:

    http://developer.imagej.net/coding-style#Ordering_of_code_blocks
ActiveImagePreprocessor: clean up style
ActiveImagePreprocessor: tweak TODO comment
OverlayService: clean up style
FillDataValues: clean up style
FillDataValues: rename fill color to "color"

Using "channelCollection" was a bit unwieldy.
FillDataValues: remove obsolete code