fix possible encoding problem (force utf8)

[sxjscience]

The reading function will report the following error in Windows.

Exception in thread "main" java.nio.charset.UnmappableCharacterException: Input length = 1
        at java.nio.charset.CoderResult.throwException(Unknown Source)
        at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
        at sun.nio.cs.StreamDecoder.read(Unknown Source)
        at java.io.InputStreamReader.read(Unknown Source)
        at java.io.BufferedReader.fill(Unknown Source)
        at java.io.BufferedReader.readLine(Unknown Source)
        at java.io.BufferedReader.readLine(Unknown Source)
        at scala.io.BufferedSource$BufferedLineIterator.hasNext(BufferedSource.scala:72)
        at scala.collection.Iterator$class.foreach(Iterator.scala:893)
        at scala.collection.AbstractIterator.foreach(Iterator.scala:1336)
        at scala.collection.generic.Growable$class.$plus$plus$eq(Growable.scala:59)
        at scala.collection.mutable.ListBuffer.$plus$plus$eq(ListBuffer.scala:183)
        at scala.collection.mutable.ListBuffer.$plus$plus$eq(ListBuffer.scala:45)
        at scala.collection.TraversableOnce$class.to(TraversableOnce.scala:310)
        at scala.collection.AbstractIterator.to(Iterator.scala:1336)
        at scala.collection.TraversableOnce$class.toList(TraversableOnce.scala:294)
        at scala.collection.AbstractIterator.toList(Iterator.scala:1336)```

This PR should solve this problem by explicitly reading as UTF8 encoding.

[sxjscience]

Met by @ShengruiLYU when doing the UROP project

[sxjscience]

@clairepchen @chzhour

[jef33]

This is fixed in 2.0