 * FULL_ADVERB(string pattern)
 *
 * Returns the full adverb is you only supply a part of an adverb. This allows
 * a player to type "smile cun" and this routine will convert that "cun" into
 * the complete adverb "cunningly". Note that the pattern should have at least
 * three characters to be allowed. If the adverb is not found, an empty
 * string "" will be returned.
