Deactiveted ADIOS1 Attribute test
Solved clang-format format and camelCase issues

Bug fix in Collective metadata serialization using threads
Added more API functions in Python bindings

InquireVariable/Attribute working for valid name, but returning invalid
type

ADIOS constructor now has host language so bindings can change define
this at the constructor level

Separated C bindings from C glue (added) for languages using C-API (e.g.
Fortran)

* Support PutDeferred() in ADIOS1 writer

* added PerformPuts() to ADIOS1Writer

* refactor toolkit/interop/adios1/ADIOS1Common in preparation for having separate Write and Read classes

* Working towards ADIOS1 Reader. Changes the Engine.BeginStep() signature for all engines.

examples/hello/bpTimeWriter/helloBPWriteStep.cpp

examples/hello/bpWriter/hellBPPutDeferred.cpp

Callback Signature classes extend Operator
Operators can be used per Variable, IO or Engine

Continue refactoring IO, ADIOS classes

BP3 Deserialization:
Getting subfile seeks and intersection info
Set host language in bindings for row-major and zero-index info

Passed ctest (MPI and nonMPI) excluding ADIOS1 engine, and Python bindings
HDF5, C bindings and C++ tests working
Introduced BeginStep EndStep functions
Renamed IO GetVariable/Attribute to InquireVariable/Attribute

Getting and defining available Variables at Open
Storing Variable position in Metadata, added to VariableBase
mpidummy: Added support for MPI_Reduce, MPI_Gatherv
Added utils and BPLS

Implemented basic buffer reading functionality
Added threading for bp serialization/deserialization
Refactored MPI functionality
Engine is now a reference
Initial Read API

First working examples
To do:
Resolve conflicts
Add tests after merging with current master

Added GetVariableBase* in IO needed by C bindings and real-time
applications, nullptr is a valid state in return.

Added c bindings test under testing/adios2/bindings/c
Updating ReadMe.md to include ADIOS2_USE_C for C bindings

Fixed conflicts for clean compilation
Fixed clang-format
Adding free in C example

Added working example examples/hello/bpWriter/helloBPWriter.c
Changed Engine signature to resolve Write void* at runtime (required by
C bindings).

To do:
CMake infrastructure
Testing

Makefile compiles

To do:
CMake infrastructure
Verify struct adios2_Engine  forward declaration
Add tests

Refactored IO, Variable class due to common functionality