Merge branch '#18-WithoutVariants' into 'master'

src/main/java/teetime/framework/pipe/SingleElementPipe.java

...java/teetime/framework/pipe/SingleElementPipeFactory.java

src/main/java/teetime/framework/pipe/SpScPipe.java

src/main/java/teetime/framework/pipe/SpScPipeFactory.java

...in/java/teetime/framework/pipe/UnorderedGrowablePipe.java

.../teetime/framework/pipe/UnorderedGrowablePipeFactory.java

src/main/java/teetime/framework/signal/ISignal.java

src/main/java/teetime/framework/signal/StartingSignal.java

...main/java/teetime/framework/signal/TerminatingSignal.java

src/main/java/teetime/framework/signal/ValidatingSignal.java

...etime/framework/validation/AnalysisNotValidException.java

...a/teetime/framework/validation/InvalidPortConnection.java

src/main/java/teetime/stage/Cache.java

src/main/java/teetime/stage/Clock.java

src/main/java/teetime/stage/CollectorSink.java

src/main/java/teetime/stage/Counter.java

src/main/java/teetime/stage/ElementDelayMeasuringStage.java

...n/java/teetime/stage/ElementThroughputMeasuringStage.java

src/main/java/teetime/stage/FileExtensionSwitch.java

src/main/java/teetime/stage/InitialElementProducer.java