Revision 1730103

PIVOT-985:  Fix the ColorUtilities.decodeColor method to deal with the two
"standard" Java color names that didn't actually work:  "darkgray" and
"lightgray" because their static field names are mixed case (as in
"darkGray") which wouldn't match our search using the lower case string.

Put in special cases for these two, plus support for the British
spellings (as in "darkgrey" and "lightgrey").

Modify one of the tutorials to test this functionality (changing "red"
to "lightGray").

Note: the other issue PIVOT-984 about supporting X11/CSS3 color names
could supercede this small fix, but I felt it was worth getting this
into the 2.0.4 branch, since the new colors wouldn't happen until 2.1.

This is a merge of revision 1730100 from "trunk" to "branches/2.0.x".