Init folly and set logtostderr in sample binary
Init folly and set logtostderr in sample binary

Summary:
By default log messages aren't set to go to stderr
https://github.com/google/glog/blob/5c576f78c49b28d89b23fbb1fc80f54c879ec02e/src/glog/logging.h.in#L1476

Reviewed By: siyengar

Differential Revision: D15145787

fbshipit-source-id: b1de63d840e58cc5eb7fa91b84513cd09a1deeae

facebookincubator/mvfst,facebookincubator/mvfst,facebookincubator/mvfst,facebookincubator/mvfst,facebookincubator/mvfst