Setting DYLD_LIBRARY_PATH may lead to crashes

[athas]

After installing Bohrium with the Python bridge (#1), I can run code with the OpenMP backend just fine. However, I get an error when I try to use the OpenCL backend:

$ BH_STACK=opencl python2 -c "import bohrium as bh; print(bh.bh_info.runtime_info())"
Cannot load library: dlopen(/usr/local/Cellar/bohrium/0.8.10/lib/libbh_ve_opencl.dylib, 2): Symbol not found: __cg_jpeg_resync_to_restart
  Referenced from: /System/Library/Frameworks/ImageIO.framework/Versions/A/ImageIO
  Expected in: /usr/local/lib/libJPEG.dylib
 in /System/Library/Frameworks/ImageIO.framework/Versions/A/ImageIO
libc++abi.dylib: terminating with uncaught exception of type std::runtime_error: ConfigParser: Cannot load library
Abort trap: 6

The reason seems to be that /usr/local/lib/libJPEG.dylib (which is installed via Homebrew, probably as the dependency of something else) takes precedence over the one at /System/Library/Frameworks/ImageIO.framework/Versions/A/Resources/libJPEG.dylib, because of Bohrium's instructions to set

export DYLD_LIBRARY_PATH="/usr/local/lib:$DYLD_LIBRARY_PATH"

After unsetting this variable, Bohrium (with the OpenCL backend) seems to work. Why is this environment variable necessary? It seems very fragile.