Reorder APIs in api-ref doc for v3 users
Reorder APIs in api-ref doc for v3 users

This patch reorders the APIs listed in the api-ref doc for v3 users so
that we have APIs documented in the following order:

- list users
- create user
- show user
- update user
- delete user
- list user groups
- list user projects
- change passwd

The rationale behind the change is that we want the order of API docs
for all resources to be consistent and easy to navigate. This patch
reorders the users APIs so that:

- Plural form of resources comes always come before singlar form because
  it has a unique URI;
- APIs about a specific resource (usually with an ID) are documented
  in the order of CRUD (create, retrieve, update and delete);
- All other helper APIs are documented at the end and they are grouped
  based on resource URIs when appropriate.

Change-Id: Ie594a45a51064a5f9089e2663bd970f10707ffaa

rajalokan/keystone,mahak/keystone,rajalokan/keystone,mahak/keystone,openstack/keystone,mahak/keystone,openstack/keystone,ilay09/keystone,openstack/keystone,ilay09/keystone,rajalokan/keystone,ilay09/keystone