cmake ghc_filesystem examples

ElyPrismLauncher/ElyPrismLauncher CMakeLists.txt :361 

find_package(ghc_filesystem QUIET)

PolyMC/PolyMC CMakeLists.txt :210 

find_package(ghc_filesystem QUIET)

fn2006/PollyMC CMakeLists.txt :334 

find_package(ghc_filesystem QUIET)

unmojang/FjordLauncher CMakeLists.txt :350 

find_package(ghc_filesystem QUIET)