New state for DPU execution - preprocessed = indicate that some
pre-processor has been executed but the DPU execution itself has not
started yet
PipelineWorker class replaced split into more specific classes
backend.Server class split
PipelineWorker removed, PipelineEvents refractored
Unused import removed
Spring version property moved from Commons-App to Intlib so backend and
frontend can access it
Backend update to support test that use Spring, test case for
backend.execution.dpu.impl.Configurator, minor bug fixes
Events in backend.dpu.event merged into two events.
Engine related events moved from backend.execution to
backend.execution.event
Merge branch 'master' of https://github.com/mff-uk/intlib.git

Conflicts:
	backend/src/main/java/cz/cuni/xrg/intlib/backend/communication/Server.java
Context commented code removed
Merge branch 'master' of https://github.com/mff-uk/intlib.git

Conflicts:
	backend/src/main/java/cz/cuni/xrg/intlib/backend/context/Context.java
Definition for Input/Output DataUnit annotation
ConfiguratorTest disabled
Edge's field and getter/setter renamed from DataUnitName to Script
Compilation problem fix
Frontend: AppEntry - Unused code and import removed, uncaught exceptions
are logged
InputDataData annotation takes 'Input' as default name, package with
annotation is automatically exported from application
DPUTemplateRecord unused methods removed, DataUnitMerger log it's
activity, pipeline executor log 'successful/failed' instead of
'finished'
Update dialog for DataUnit's mapping, added classes for examining the
annotation of given instance, EdgeCompiler for translating between
Edge's script and Mapping's data structure