Add a few test for the core functions.

More test will be added later.
Add `Event`, a helper class for testing order of events.
Use Scala 2.10.1 - fixes scaladoc bugs.

Scaladoc 2.10.0 doesn't include default values for function arguments.
See https://issues.scala-lang.org/browse/SI-4922
Moved to Scala 2.10.2.
Modified `toCol` to use much more generic `CanBuildFrom`.
Merge branch 'master' of github.com:ppetr/scala-conduit