Sasha/ev readme (#5884)
Sasha/ev readme (#5884)

* Updated the README

- Fixed obsolete links
- Removed heavy SSH focus
- More modern language to describe what Teleport is

* Update links

Co-authored-by: Ev Kontsevoy <828e64e13e3fc71511c7785f33117be2da9e4fb7@kontsevoy.com>
gravitational/teleport,gravitational/teleport,gravitational/teleport,gravitational/teleport,gravitational/teleport,gravitational/teleport