Revised contributing.md, edited docs (#1951)

* Added Overview page

* Revised Getting Started page

* Minor revision

* Edited readme, minor modifications to docs

* Removed sweep.yaml, .devcontainer, .ergomake

* Moved security.md to .github, added contributing.md

* changes as per code review

* updated contributing.md

* fixed broken links & added missing links in doc, improved structure

* fixed link in wsl setup

* fixed server link, added https cloning in yarn-setup

docs/docs/contributor/server/basics/overview.mdx

@@ -5,5 +5,6 @@ sidebar_custom_props:
   icon: TbEyeglass
 ---
 
+We use NestJS on the backend. 
 
-WIP
+More details coming Soon