Added test for generating profiling.json
Fixed inclusion for NLohmannJson json.hpp in Test
Tested resulting profiling.json on R (jsonlite), Python (json)
and C++ (json for modern C++)

1 Now IO (replaced Method) and is the factory for Variables and Engines
2 Reduced core components to user-public objects only
3 Moved and reorganized all helper functions to helper directory
4 Engines are now lightweight (except for ADIOS1Reader WIP) using MACRO
5 HF5Common and ADIOS1Common (except for Readers WIP) are now part of the toolkit so they can be reused by Engines
6 TransportMan is a new layer for transport management (file is default)
7 DataMan will be implemented under toolkit/transportman/dataman
8 Template separation (tcc and inl) applied all over the code
9 Improved Doxygen documentation

Runtime Issues:
DataMan library compilation (cacheman)
ADIOS1 Warning
TestADIOSInterfaceWrite catches exceptions

Fixing const-correctness in BP1
Changed CodingGuidelines to include clang-format information