Start work on the 0.15.0 release notes
Removed duplicated instructions for clarity
Deleted outdated build instructions

I think something similar to these should be available, but
anyone following these and also trying to use the backported packages
is likely to make a mess at the moment.
Merge pull request #4764 from joehealy/further_debian_doc_changes

Further debian doc changes
Refine the top paragraph a bit