Rework of HeavyDataController and HDF5Controller to remove extra code and move HeavyDataController away from being too dependent on hdf5 style
XdmfFunction now supports negative numbers in addition to the - operator
Reworked the interaction between array references and reading
Cleaned up some warnings that showed up in pedantic
Adjusted mpi tests to test against the MPIEXEC variable as opposed to hard calling mpirun
Still needs to be changed to work better with Cray mpi style execution
Updates to XdmfArrayType to allow for signed and floating point checking
General test and Documentation updates

Fully support parsing of nested xincludes in Xdmf files. Add a test to ensure
this remains supported - the test contains an xinclude to an element in a
separate file that itself is another xinclude to an XdmfInformation.

wrapped function and subset into superclass XdmfArrayReference to allow for easier implementation of new array references

fixed documentation to account for new dsm folder; adjusted the test for XdmfError; disabled the WriteHugeArray test

Added subset; modified Array's interaction with Function; added new functionality to XdmfInformation subarrays; adjusted documentation to make more uniform

made changes for preparations to push to master; still need to finish documentation changes and line length changes

Since XdmfGridCollection inherit from XdmfDomain, the typemap for XdmfItem
should attempt a dynamic cast to XdmfGridCollection before XdmfDomain.
Added a python test to ensure that these typemap changes will continue to
work in the future.

changes for file splitting and functions along with assorted changes to XdmfFortran for possible speed increases

changes to file splitting, hyperslab not completely working yet. changes to Fortran to allow for polylines and releasing data after standard write

This reverts commit f386e633.

Remove some warnings related to hidden functions.

Graphs are stored in compressed sparse row format (XdmfSparseMatrix).
Added ability to partition graphs in XdmfPartitioner.
Added tests for new sparse matrix and graph classes.

Add tests for I/O of strings (to hdf5 and xml).
Fix bug in XdmfExodusReader when reading grid centered data.
Add string I/O in python and add tests.

Modified writer to utilize hyperslabs to write in parallel to file.
Updated DSM to newest version (0.9.9).
Modified DSM test to write in parallel to DSM buffer.
Add test for new hyperslab writing mode.

Slightly improves compile time on gcc.
Get rid of mHaveArray and mHaveArrayPointer - rely on blank in variant.
This reduces code and makes logic easier to understand.