Identity v2.0/tenants example shows v2.0/tokens/tenants

The call to the identity api v2.0/tenants is shown in the example using
v2.0/tokens/tenants and should be as the title v2.0/tenants

Closes-bug: #1334285
Change-Id: Ie8db3f577fc98decdeb2be36929c03f61f09abd8
Removes irrelevant links to HTTP definition.

Removes sentence "For a complete description of HTTP 1.1 header definitions, see Header Field Definitions." from several pages on ch02, object-api, stored in wadl files

Change-Id: If574799dddbd79d49984041e9d51603feae2d669
Closes-bug: #1332008
Merge "Removes irrelevant links to HTTP definition."
Merge "Identity v2.0/tenants example shows v2.0/tokens/tenants"