Currently the auth mechanism doesn't support permissions of range
request. It just checks exact matching of key names even for range
queries. This commit adds a mechanism for setting permission to range
queries. Range queries are allowed if a range of the query is [begin1,
end1) and the user has a permission of reading [begin2, range2) and
[begin1, end2) is a subset of [begin2, range2). Range delete requests
will follow the same rule.
This commit adds a new subcommand "user add" to etcdctlv3. With the
command users can create a user for the authentication.
Example of usage:
$ etcdctlv3 user add user1
Password of user1:
Type password of user1 again for confirmation: