Minor spelling corrections in documentation.
Added example using subtype unifier type class.
Merge pull request #25 from travisbrown/master

Spelling and a new example
Added .jvmopts for sbt-extras.
Bumped plugin versions.
Added HKernel.
Merge remote-tracking branch 'github/master'
Revert "Bumped plugin versions."

This reverts commit 827d8ee0a32ec54e3cfbdc07b8b58211aa2a8790.
Merge branch 'master' into scala-2.9.x
No implicit classes on 2.9.x.