Miscellaneous cleanup in DerivedCodec and ImplicitCodec
Lots of new ScalaDoc, added withContext to Codec
Update CHANGELOG for 1.5 release
Fix compiler warning
Bump version
Fix typo
Merge pull request #34 from kanterov/fix-typo

Fix typo in examples
More examples of implicit expansion errors
Merge branch 'master' into topic/shapeless-2.1