extend-stages - removing intro paragraph that doesn't seem to add any

real content

docs/extend-stages.md

 # Extension Life cycle
 
-The CiviCRM ecosystem is built on the belief that non-profit
-organizations can serve themselves best by collaborating in development of their
-data-management applications.  As staff, volunteers, and consultants for
-non-profit organizations, we can share our new enhancements and extensions --
-and build a richer whole for the entire ecosystem.
-
-Of course, this sharing arrangement means that many members of the community
-have a split role, e.g.
-
--   Sometimes, we are consumers. We want to quickly browse the available
-    extensions, pick the ones which look best, and install them. We
-    expect these to just work -- both now and going forward (with future
-    upgrades).
--   Sometimes, we are developers.  We enjoy building great functionality, and we
-    want to invite people to use our products, but we need to juggle the
-    publishing tasks (like testing and maintenance releases) with the goals
-    and resources provided by our bosses and clients.
-
-The purpose of this document is to describe the process of publishing
-extensions through the CiviCRM ecosystem.
+This document describes the process of publishing extensions within the CiviCRM ecosystem.
 
 ## Definitions