Added XdmfExodusReader to utils directory
Added exodusii and netcdf sources to xdmf to support XdmfExodusReader.cxx and XdmfExodusConverter
Modified install locations for executables to prefix/bin
Modified install location for python scripts to be correct for all platforms (was previously incorrect for OS X)
Adjusted python install process to work for all Xdmf incantations, irregardless of how much is built (python was previously working only when Utils was built)
Python testing automatically sets correct paths and works automatically
Major improvement to XDMFConfig.cmake file for applications that build against Xdmf
More correct information in XDMFConfig.cmake --- e.g. no need to include hdf5 directories in addition to xdmf, an INCLUDE_DIRECTORIES(XDMF_INCLUDE_DIRS) should be sufficient when building against Xdmf
Fixes to Xdmf.h to include newer Xdmf classes like XdmfSet