The CMake files in this project and its submodules are not up to scratch with modern CMake practices (as outlined here and here).

A to-do list of low-hanging fruit:

• Remove all use of global functions like include_directories and link_directories
• Add PUBLIC and PRIVATE to target properties and linking (using PRIVATE as default)
• Remove use of source file globbing
• Look for and avoid direct modification of CMAKE_CXX_FLAGS
• Add aliases for Faasm/ Faabric libraries with faasm:: and faabric::
• Remove spurious variables like LIB_FILES and HEADERS, instead list things directly in add_library where possible
• Make sure we install all dependencies under CMAKE_INSTALL_PREFIX
• Instead of target_link_directories separately in faabric_lib, add a link to CMAKE_INSTALL_PREFIX/include
• Consider using a CMake linter like cmake-lint or polysquare-cmake-linter

The sgx directory is a law unto itself and can be excluded from this tidy-up for now.