Moved DiagrammedExp and DigrammedExprMacro from scalactic package to scalatest package.
Described new macro behavior in Assertions Scaladoc.
Fleshed out Scaladoc for DiagrammedAssertions.
Fleshed out Scaladoc for Requirements.
Fleshed out Scaladoc for Snapshots and friends.
Added matchPattern Scaladoc.
Added some comments to BooleanMacro to explain macro code.