etcd: remove unnecessary flag desc
pkg: move DeprecatedFlag to new package
etcd: pass flagset into setFlagsFromEnv
etcd: export SetFlagsFromEnv
etcd: rewrite SetFlagsFromEnv test to use custom flagset
pkg: move SetFlagsFromEnv to pkg package
test: alphabetize list of testable packages
Merge pull request #1167 from bcwaldon/move-flag-code

Move flag-related code into new pkg package