Remove environs.{VerifyStorage,CheckEnvironment}

environs.VerifyStorage was being called at
Bootstrap time; we're getting rid of provider
storage so this needs to go. Also, the related
CheckEnvironment function (which checks the
contents of the bootstrap-verify file) is only
called in tests.
Merge pull request #815 from axw/no-verifystorage-take2

Remove environs.{VerifyStorage,CheckEnvironment}

environs.VerifyStorage was being called at
Bootstrap time; we're getting rid of provider
storage so this needs to go. Also, the related
CheckEnvironment function (which checks the
contents of the bootstrap-verify file) is only
called in tests.

Exact copy of #575, which the bot seems to be ignoring (maybe because I closed/reopened)