Attempting to solve HDF5 failed tests on summitdev

Remove cdash warnings for unused variables, type cast (including HDF5
char vs. int8) and virtual functions overloads.

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)

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

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

signed char needed by int8_t in C bindings
Added tests

Refactored IO, Variable class due to common functionality

To do: 
Debug hello_datamanWriter non-MPI version

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

Some code for joined array reading in adios1 engine, incomplete. Rather should support it in adios1 itself.
Committed only to have a working Write/Read API so that we can have examples with global arrays finalized.