Add: Founding principles of NHS-R

[Lextuga007]

From closing talk by @ChrisBeeley in 2020 the slide

NHS-R is free at the point of delivery for analysts
 - We don't charge for training
 - We don't charge for software
 - We don't charge for mentoring and code review
 - We **share**

NHS-R promotes the use of open source
NHS-R promotes sharing of code and data
NHS-R promotes publishing under open source licences
NHS-R branded solutions will _always_ be open source

NHS-R works across organisational boundaries
 - NHS-R activities are carried out with no preference or prejudice applied to any region or organisation

NHS-R is a community
 - We recognise our members in the fellowship programme
 - But anybody can be a leader (book group, mentoring, Shiny, SPC, hacktoberfest, hackathons...)