initial refactory

Refactoring corsika/core corsica/framework/geometry

...

refactory: corsika/framework/sequence

refactorying...

header.h -> header.hpp + other refacorying...

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refactory media directory...

refactory: corsika/processes

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refactoring...

testing...

Sibyll headers...

Pythia headers...

module sub-dir

some floating cc files around

eliminate relative include paths on top directories

fixing include file paths, remove quotes from include directives, fix remaining include guards and correct file names ...

unit tests: fixing include file paths, remove quotes from include directives, fix remaining include guards and correct file names ...

corsika/detail inclusion

corsika/detail changes

corsika::secondary_namespaces supressed in favor of detail

more include guards, relative file path, etc ...

nested class promotion to corsika::detail

Inteface to Pythia

one more relative path...

eliminating files...

dependencies managment...

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dependencies refactory

adding corsika/modules and catch2

build scripts for UrQMD

make modules compile

cmake

first working vesion of new fwk

need to generate some header files

build scripts for dependencies

sibyll works now

proper file endings in many places

include proposal in build system
incl. proposal in cmake build. fix several problems.

added a few more basic unit-tests for Examples. This is supposed to catch future failures of this type.

 On branch 188-sibyll-decay-of-sigmabar0-yields-sigmabar0
 You are currently cherry-picking commit 9c650baf.

 Changes to be committed:
	modified:   Documentation/Examples/boundary_example.cc
	modified:   Documentation/Examples/cascade_example.cc
	modified:   Documentation/Examples/vertical_EAS.cc
	modified:   Processes/Sibyll/Decay.cc
	modified:   Processes/Sibyll/Decay.h
	modified:   Processes/Sibyll/Interaction.cc
	modified:   Processes/Sibyll/Interaction.h
	modified:   Processes/Sibyll/sibyll2.3c.f
	modified:   Processes/Sibyll/testSibyll.cc