Align introduced terminology (and index) with heading

chapters/connectors.tex

@@ -879,7 +879,7 @@ \subsection{Generation of Connection Graph Equations}\label{generation-of-connec
   If there are n selected roots in a subgraph, then optional spanning-tree edges have to be removed such that the result shall be a set of n spanning trees with the selected root nodes as roots.
 \end{enumerate}
 
-After this analysis, the \firstuse[connection equations!overconstrained]{connection equations} are generated in the following way:
+After this analysis, the \firstuse{connection graph equations}\index{connection equations!connection graph} are generated in the following way:
 \begin{enumerate}
 \item
   For every optional spanning-tree edge (i.e., a \lstinline!connect(A, B)! equation), in one of the spanning trees, the connection equations are generated according to \cref{generation-of-connection-equations}.