hgk: add black and blue as preferred colors

hgk: add black and blue as preferred colors

--- a/contrib/hgk	Mon Dec 10 00:35:04 2007 +0000
+++ b/contrib/hgk	Mon Dec 10 12:16:59 2007 -0600
@@ -3844,7 +3844,7 @@
 
 set colors {green red blue magenta darkgrey brown orange}
 set authorcolors {
-    deeppink mediumorchid blue burlywood4 goldenrod slateblue red2 navy dimgrey
+    black blue deeppink mediumorchid blue burlywood4 goldenrod slateblue red2 navy dimgrey
 }
 
 catch {source ~/.hgk}