Clean up standard topologies to use build
fix Singleton.__call__ error

fix Singleton.__call__ error
Merge pull request #333 from mininet/devel/buildtopo

Clean up standard topologies to use build
Merge pull request #344 from bentenshan/patch-1

fix Singleton.__call__ error
Fixing Node.monitor() to read entire prompt marker.

Applying @cdburkard fix to #322
merging master