+/**
+ * A colour scheme based on a selected Hidden Markov Model. The colour is
+ * <ul>
+ * <li>white for a gap</li>
+ * <li>red for an insertion</li>
+ * <li>orange for negative information content</li>
+ * <li>white to blue for increasing information content</li>
+ * </ul>
+ * where information content is the log ratio
+ *
+ * <pre>
+ * log(profile match emission probability / residue background probability>
+ * </pre>
+ *
+ * using global ('Uniprot') background frequencies for residues.
+ *
+ * @author tzvanaalten
+ *
+ */