added network + fix and refactoring of resource demand estimation

...x/src/tools/descartes/pmx/core/builder/IModelBuilder.java

.../src/tools/descartes/pmx/core/builder/pcm/PCMBuilder.java

.../tools/descartes/pmx/core/builder/pcm/PCMSEFFFactory.java

...ols/descartes/pmx/core/filter/PerformanceModelFilter.java

...artes/pmx/core/filter/PerformanceModelFilterAppender.java

.../filter/resourcedemands/AbstractResourceDemandFilter.java

.../filter/resourcedemands/InternalResourceDemandFilter.java

...pmx/core/filter/resourcedemands/ResourceDemandFilter.java

...mx/core/filter/resourcedemands/ResourceDemandFilter2.java

.../filter/resourcedemands/ResourceDemandFilterAppender.java