Adds a de-interlace module and stuff

Adds a module to de-interlace when converting a video. It's enabled by a new configuration option.
Fixes some bugs in the letterbox cropper
Adds mpeg4 to video formats

src/main/java/net/knarcraft/ffmpegconverter/converter/WebVideoConverter.java

@@ -53,7 +53,7 @@ public class WebVideoConverter extends AbstractConverter {
         List<ConverterModule> modules = new ArrayList<>();
 
         if (this.debug) {
-            modules.add(new DebugModule(0, 0));
+            modules.add(new DebugModule());
         }
 
         //Get first streams from the file