ST. LOUIS — A teenage girl and a health teacher were shot to death and six others were injured Monday morning at Central Visual & Performing Arts High School in south St. Louis. Police confronted the gunman inside the school and killed him. The suspect, a man not yet identified, was about 20. Police haven’t said what connection, if any, he had to the school. One survivor heard him say he was “tired of everybody” in the school. His gun jammed at one point, giving kids time to escape. Authorities have not released the names of the woman and the teenage girl who died. But relatives of the woman i…