Merge pull request #76 from tzz/master

Minor fixes for DC manual
corrected omission of user edited failsafe/update
Document --self-diagnostics for cf-agent
More to come in manuals.
Some documentation about Enterprise Reporting.
Merge pull request #77 from McAtte/master

correct an omission about user edited update.cf
manuals/design-center.markdown: add note about root walkthrough