docs(chore): dinghy-enable - add tabs for Operator vs Halyard content (…

…#296)

* docs(dinghy): Make it clearer that multiple orgs for pipeline definitions are supported by dinghy

* Fix typo

* small edit

* incorporate tabs for operator vs halyard

more small edits on entire page

* pull PaC overview into "include" file

* moved a sentence.

* https://armory.atlassian.net/browse/DOC-36

L241 changed endpoint

* text explaining Stash is now Bitbucket Server

Co-authored-by: Akshay Dayal <akshay.dayal@armory.io>