Merge pull request #9 from smirolo/master

style and coverage reports
Added singleton factory constructor for FIFOIO
Added Data.isDirectionless method. Returns true if the Data (and for Bundles, all enclosed Data) has no associated direction and thus can be safely used as a struct inside a component. Intended use case is require(data.isDirectionless) in components that wish to guard against a bad constructor data input. Future commits will demonstrate this use to protect some of the ChiselUtil standard library components.
Copy changes by A. Waterman in manual over to tutorial concerning sequential memory reads
Merge branch 'master' of https://github.com/smirolo/chisel into smirolo-master

Conflicts:
	src/main/scala/Bits.scala
	src/main/scala/Bundle.scala
	src/main/scala/ChiselUtil.scala
	src/main/scala/Data.scala