Use .NET 4 in the NodaTime.Test project, so that we can run tests against the PCL configuration. There are still 3 test failures, all around the exception thrown when asking DateTimeCache for a zone it doesn't know about.
Use .NET 4 in the NodaTime.Test project, so that we can run tests against
the PCL configuration. There are still 3 test failures, all around the exception
thrown when asking DateTimeCache for a zone it doesn't know about.

malcolmr/nodatime,zaccharles/nodatime,BenJenkinson/nodatime,BenJenkinson/nodatime,zaccharles/nodatime,zaccharles/nodatime,jskeet/nodatime,zaccharles/nodatime,zaccharles/nodatime,malcolmr/nodatime,nodatime/nodatime,malcolmr/nodatime,zaccharles/nodatime,nodatime/nodatime,malcolmr/nodatime,jskeet/nodatime