Bug #908: RGW allows users to create buckets and objects with invalid names
forbid bad bucket names
Pull request ID:
Enforce strict bucket name rules in RGW.
Strict rules (culled from libs3, Amazon's documentation, and miscellaneous online discussions):
length between 3 and 63, inclusive only [a-z][0-9], and the dash character are allowed Dashes can't be at the end or the beginning.