Change output format for extinf.

Now, it'll use peg's line and column tracking. So, each extinf would
output an object with property #EXTINF + line number.

package.json

@@ -8,7 +8,7 @@
   "scripts": {
     "test": "grunt qunit",
     "prepublish": "npm run peg",
-    "peg": "pegjs src/m3u8/m3u8.pegjs src/m3u8/m3u8-generated.js",
+    "peg": "pegjs --track-line-and-column src/m3u8/m3u8.pegjs src/m3u8/m3u8-generated.js",
     "testpeg": "npm run peg && node test/pegtest.js"
   },
   "devDependencies": {

src/m3u8/m3u8.pegjs

@@ -34,7 +34,7 @@ m3uTag
 extinfTag
   = tag:'#EXTINF' ":" duration:number "," _ title:text? _ byteRange:byteRangeTag? _ file:mediaFile {
       var fileObj = {};
-      fileObj[file] = {
+      fileObj[tag + line] = {
         byteRange: byteRange,
         title: title,
         duration: duration,