variable.
* dlfcn.cc (get_full_path_of_dll): Search /usr/bin (for windows compatibility)
and /usr/lib (for UNIX compatibility) when looking for shared libraries.
* environ.cc (conv_envvars): Put back LD_LIBRARY_PATH since it is used by
get_full_path_of_dll().
* errno.cc (errmap): Map MOD_NOT_FOUND to ENOENT.
* cygmagic: Remove debugging cruft.