A new government report shows smoking by teens hit a new low last year while the popularity of electronic cigarettes and water pipes boomed.  Teen use of e-cigarettes tripled in one year to more than 13 percent.  About 9 percent of high schools students said they had tried hookahs.  But smoking of traditional cigarettes plummeted to about 9 percent.  The Centers for Disease Control and Prevention released the report Thursday.  It’s based on a national survey of about 22,000 students at middle schools and high schools, both public and private.  A government-funded study released in December found similar trends.