Add CMake option to build without HDF5

[anderkve]

As discussed in the Core meeting today, we should have a CMake option like -D WITH_HDF5 that we can set to False for users who are not interested in using the HDF5 printers.

[ChrisJChang]

Check for HDF5 libraries

if (WITH_HDF5)
find_package(HDF5 QUIET COMPONENTS C)
if(HDF5_FOUND)
include_directories(${HDF5_INCLUDE_DIR}) # for older versions of cmake
include_directories(${HDF5_INCLUDE_DIRS}) # for newer cmake
message("-- Found HDF5 version: ${HDF5_VERSION}")
if (HDF5_VERSION VERSION_GREATER 1.12 OR HDF5_VERSION VERSION_EQUAL 1.12)
message(" Enforcing API macro mapping to HDF5 version 1.10.")
set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DH5_USE_110_API")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DH5_USE_110_API")
endif()
message(" Found HDF5 libraries: ${HDF5_LIBRARIES}")
if(VERBOSE)
message(STATUS ${HDF5_INCLUDE_DIRS} ${HDF5_INCLUDE_DIR})
endif()
else()
message("${BoldCyan} X No HDF5 C libraries found. Excluding hdf5printer and hdf5reader from GAMBIT configuration.${ColourReset}")
set(itch "${itch}" "hdf5printer" "hdf5reader")
endif()
else()
message("${BoldCyan} X No HDF5 C libraries found. Excluding hdf5printer and hdf5reader from GAMBIT configuration.${ColourReset}")
set(itch "${itch}" "hdf5printer" "hdf5reader")
endif()

[anderkve]

This is now fixed by PR #582. Closing.