=doc fix unclosed quotes in docs
Merge pull request #16127 from ktoso/fix-not-closed-quotes-docs-ktoso

=doc fix unclosed quotes in docs
=doc #16134 read file as binary stream, because StreamReader expects binary
=doc New styling and logos for the documentation

* Updated CSS Styles, new logos (SVG format), New header/nav design. General colors overrides, small but safe HTML changes, new favicon.
* Updated GA snippet with addition domain, added Marketo snippet
* Made fonts consistent, styled note and warning in TS/Akka colors
Merge pull request #16139 from akka/wip-akka-docs-updated-skin-rasummer

=doc New styling and logos for the documentation
Merge pull request #16135 from 2m/wip-fix-docs-build-python3

=doc #16134 read file as binary stream, because StreamReader expects binary
=doc Link to CONTRIBUTING.md and remove obsolete dev guidelines

(cherry picked from commit 84382f06494e908a2fa5e1ab452ba0fe770ba239)
Merge pull request #16143 from akka/wip-doc-contributing-master-patriknw

=doc Link to CONTRIBUTING.md and remove obsolete dev guidelines (for validation)