Add United Diversity coop to site

Josef provided a list of clients, technologies and services in this
comment on the community forum:

https://community.coops.tech/t/our-new-www-coops-tech-jekyll-website/1167/10

I've cribbed the description and contact details from their website.

I've assumed 2 members until I find out more.

_clients/better-media.md

@@ -0,0 +1,3 @@
+---
+title: Better Media
+---

_clients/ctrl-shift.md

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+---
+title: CTRLshift
+---

_clients/media-reform-coalition.md

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+---
+title: Media Reform Coalition
+---

_clients/stir-to-action.md

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+---
+title: Stir To Action
+---

_clients/wiki-factory.md

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+---
+title: Wiki Factory
+---

_coops/united-diversity.md

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+---
+title: United Diversity
+name: United Diversity
+members: 2
+website: https://uniteddiversity.coop/
+email: josef@uniteddiversity.coop
+twitter: uniteddiversity
+github: uniteddiversity
+telephone: 07974 88 88 95
+address:
+latitude:
+longitude:
+clients:
+- stir-to-action
+- media-reform-coalition
+- campaign-for-press-and-broadcasting-freedom
+- ctrl-shift
+- better-media
+- co-operatives-london
+- wiki-factory
+services:
+- branding-and-identity
+- community-building
+- consultancy
+- graphic-design
+- ideation
+- mentoring
+- research
+- strategy
+- web-design
+technologies:
+- discourse
+- drupal
+- htmlcss
+- wordpress
+---
+
+Together We Have Everything
+
+Imagine if everyone shared some of everything they have: time, money, tools, knowledge, land, food, shelter.
+
+Together, we already have the knowledge, expertise, land, property and resources necessary to empower people, build community, develop co-ops and create commons. We just need to self-organise and start sharing.