Documentation updates

This pacthset adds:

- documentation for account
- documentation for storage luks
- reworks storage docs to new multiplexer

Preview:
http://jsafrane.fedorapeople.org/openlmi/account-doc-preview/
http://jsafrane.fedorapeople.org/openlmi/storage-doc-preview/luks.html

It depends on previous "Add LUKS scripts." pull request.