Man shot trying to rob Syracuse store owner pleads guilty in court — A Syracuse man shot while trying to rob the owner of a store in September admitted his guilt in court today.  Rayshawn Johnson, 29, pleaded guilty before state Supreme Court Justice John Brunetti to felony charges of attempted first-degree robbery, attempted second-degree criminal possession of a weapon and third-degree criminal possession of a weapon.  Johnson admitted being armed with a knife when he tried to rob an employee of the Los Amigos convenience store at 204 W. Brighton Ave. Sept. 27.  Assistant District Attorney Kari Armstrong said Johnson was threatening owner Ruben Colon with a large knife when Colon pulled out a gun to defend himself.