[css-text-4] Add myself as a co-editor

Author: frivoal

css-text-4/Overview.bs

@@ -11,6 +11,7 @@ Previous Version: https://www.w3.org/TR/2015/WD-css-text-4-20150922/
 Editor: Elika J. Etemad / fantasai, Invited Expert, http://fantasai.inkedblade.net/contact, w3cid 35400
 Editor: Koji Ishii, Google, kojiishi@gmail.com, w3cid 45369
 Editor: Alan Stearns, Adobe Systems, stearns@adobe.com, w3cid 46659
+Editor: Florian Rivoal, Invited Expert, https://florian.rivoal.net, w3cid 43241
 Abstract: This module defines properties for text manipulation and specifies their processing model. It covers line breaking, justification and alignment, white space handling, and text transformation.
 Ignored terms: segment break, segment breaks
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