poly2tri: include stdexcept in each file throwing an std::exception.

polygon/poly2tri/common/shapes.cc

@@ -30,7 +30,7 @@
  */
 #include "shapes.h"
 #include <iostream>
-#include <exception>
+#include <stdexcept>
 
 namespace p2t {
 

polygon/poly2tri/sweep/sweep.cc

@@ -28,11 +28,11 @@
  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-#include <stdexcept>
 #include "sweep.h"
 #include "sweep_context.h"
 #include "advancing_front.h"
 #include "../common/utils.h"
+#include <stdexcept>
 
 namespace p2t {