fix for possible colour category entry with no categories.
fix for possible colour category entry with no categories.

git-svn-id: 69491b240b1229d41c2c72941f658cbe2c7afb5a@85 fab39794-68fa-11de-a719-67d2479c5694

farnulfo/java-libpst,mureinik/java-libpst,Yariki/java-libpst,casimirenslip/java-libpst,Yariki/java-libpst,mureinik/java-libpst,farnulfo/java-libpst