Backport Object Storage Admin Guide from trunk

Backport doc/src/docbkx/openstack-object-storage-admin/*

With small updates to bk-objectstorage-adminguide.xml metadata so
that it mentions Folsom instead of trunk.

Patchset updates pom.xml to 1.5.2, build works.

Change-Id: Ia92f53b84d14e73e0799b4d98acef591eeff73cb