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.

- Added examples/groupless/multistep writer example to the build
- Added ADIOS1 reader but it does not work yet
- Added heat transfer example reader

Use the HDF5_C_INCLUDE_DIRS instead of HDF5_INCLUDE_DIRS

Allow json.hpp to be used with gcc 4.8.5

There are a few issues with this that prevent it from being accepted upstream but it's fine for how we use it.

Add asserts to disabled tests.

This will ensure that even if they are run they will fail

Add read validation to engine tests

Fixed a bug in CacheMan for cleaning variables after a time step is finished

Fix typos in engine tests

Fix typo in ADIOS1 test

Simplify test source

Improved CacheMan to allow caching multiple time steps

Refactoring of engine tests