added documents and updatedExisting to last error

Conflicts:
	project/ReactiveMongo.scala
Merge branch 'fixidixy' of github.com:pchlupacek/ReactiveMongo into pchlupacek-fixidixy

Closes PR #42 (added documents and updatedExisting to last error).

Conflicts:
	driver/src/main/scala/core/commands/commands.scala