Top level cmake: add _GNU_SOURCE definition on cygwin [only for now] to get strptime, and gnu specific glob flags.
Top level cmake: add _GNU_SOURCE definition on cygwin [only for now] to get strptime, and gnu specific glob flags.

quantcast/qfs,quantcast/qfs,quantcast/qfs,quantcast/qfs,quantcast/qfs,quantcast/qfs,quantcast/qfs,quantcast/qfs