README: "About matrix" updates

- remove redundant "where's the spec" section: this would belong in "About
matrix", but it's already there.

- E2E is in beta rather than dev

README.rst

@@ -86,7 +86,7 @@ report any bugs via github.
 
 Thanks for using Matrix!
 
-[1] End-to-end encryption is currently in development - see https://matrix.org/git/olm
+[1] End-to-end encryption is currently in beta.
 
 
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@@ -593,13 +593,6 @@ Then update the `users` table in the database:
         WHERE name='@test:test.com';
 
 
-Where's the spec?!
-==================
-
-The source of the matrix spec lives at https://github.com/matrix-org/matrix-doc.
-A recent HTML snapshot of this lives at http://matrix.org/docs/spec
-
-
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 ===================