#223 Change type of lastModified to number

src/android/src/main/java/com/RNFetchBlob/RNFetchBlobFS.java

                 stat.putString("path", target.getPath());
                 stat.putString("type", target.isDirectory() ? "directory" : "file");
                 stat.putString("size", String.valueOf(target.length()));
-                int lastModified = (int) target.lastModified();
-                stat.putInt("lastModified", lastModified);
+                String lastModified = String.valueOf(target.lastModified());
+                stat.putString("lastModified", lastModified);
 
             }
             return stat;

src/fs.js

     RNFetchBlob.stat(path, (err, stat) => {
       if(err)
         reject(new Error(err))
-      else
+      else {
+        if(stat)
+          stat.lastModified = parseInt(stat.lastModified)
         resolve(stat)
+      }
     })
   })
 }