sbtの起動シェルスクリプトと関連ファイルを bin/ ディレクトリに移動させるのを忘れていた

@inakata 先生、sbtをbinディレクトリに移動させるのを忘れていたのは私のミスです。すいません。この pull requestをMergeしてもらってから、

```
$ git pull
```

すれば変更が取り込まれます。Ruby.scalaは前のpull requestで、

* src/main/scala/com/github/inakata/ruby_scala/Ruby.scala
* src/main/scala/com/github/inakata/ruby_scala/RubyParser.scala
* src/main/scala/com/github/inakata/ruby_scala/TracableParsers.scala

に分割するようにしました（これについては事前に確認するべきでした。申し訳ありません）。実行するときは、単に `bin/sbt` でOKです。以下にMac OSでの実行サンプルを貼付けておきます(Linuxでも同様に動くはずです)。

```
 ~/git/ruby_scala (git master) 
[mizushima]$ bin/sbt
Loading /Users/mizushima/git/ruby_scala/bin/sbt-launch-lib.bash
[warn] The global sbt directory is now versioned and is located at /Users/mizushima/.sbt/0.13.
[warn]   You are seeing this warning because there is global configuration in /Users/mizushima/.sbt but not in /Users/mizushima/.sbt/0.13.
[warn]   The global sbt directory may be changed via the sbt.global.base system property.
[info] Loading project definition from /Users/mizushima/git/ruby_scala/project
[info] Set current project to ruby_scala (in build file:/Users/mizushima/git/ruby_scala/)
> run heredoc.rb
[info] Compiling 3 Scala sources to /Users/mizushima/git/ruby_scala/target/scala-2.10/classes...
[warn] /Users/mizushima/git/ruby_scala/src/main/scala/com/github/inakata/ruby_scala/TracableParsers.scala:19: match may not be exhaustive.
[warn] It would fail on the following input: Error(_, _)
[warn]         result match {
[warn]         ^
[warn] there were 37 feature warning(s); re-run with -feature for details
[warn] two warnings found
[info] Running com.github.inakata.ruby_scala.RubyParser heredoc.rb
[6.1] parsed: (Heredoc("AAAA
") + Heredoc("BBBB
"))
[success] Total time: 27 s, completed 2013/11/10 9:04:48
> run heredo
<arg>   
> run heredoc.rb
[info] Running com.github.inakata.ruby_scala.RubyParser heredoc.rb
[6.1] parsed: (Heredoc("AAAA
") + Heredoc("BBBB
"))
[success] Total time: 1 s, completed 2013/11/10 9:05:00
> compile
[success] Total time: 0 s, completed 2013/11/10 9:05:11
```