Add link to scaladoc in README.md
Merge pull request #76 from jvns/patch-1

Add link to scaladoc in README.md
Update required version of sbt in README
Merge pull request #77 from jvns/patch-2

Update required version of sbt in README
Update README.md

adding Kentaroh Takagaki (@ktakagaki) as a contributor.
Merge remote-tracking branch 'scalanlp/master'