Restore (R) in README.md

According to phone meeting decision.

README.md

@@ -5,7 +5,7 @@ This repository contains the Modelica Language Specification, hosted at https://
 
 ## Description
 
-Modelica is a language for modeling of cyber-physical systems, supporting acausal connection of components governed by mathematical equations to facilitate modeling from first principles.
+Modelica® is a language for modeling of cyber-physical systems, supporting acausal connection of components governed by mathematical equations to facilitate modeling from first principles.
 It provides object-oriented constructs that facilitate reuse of models, and can be used conveniently for modeling complex systems containing, e.g., mechanical, electrical, electronic, magnetic, hydraulic, thermal, control, electric power or process-oriented subcomponents.
 
 ## Releases