Added Checkstyle to build process and fixing checkstyle to all com.src.jpexs classes

src/com/jpexs/decompiler/flash/gui/MainFrameClassic.java

@@ -51,6 +51,7 @@ public final class MainFrameClassic extends AppFrame implements MainFrame {
                 flashPanel = new FlashPlayerPanel(this);
                 flashPanel2 = new FlashPlayerPanel(this);
             } catch (FlashUnsupportedException fue) {
+                //ignored
             }
         }