* autodetect .idx files for vobsub autodetection

src/input/subtitles.c

@@ -57,7 +57,7 @@
 /**
  * The possible extentions for subtitle files we support
  */
-static const char * sub_exts[] = {  "utf", "utf8", "utf-8", "sub", "srt", "smi", "txt", "ssa", NULL};
+static const char * sub_exts[] = {  "utf", "utf8", "utf-8", "sub", "srt", "smi", "txt", "ssa", "idx", NULL};
 /* extensions from unsupported types */
 /* rt, aqt, jss, js, ass */