#1141 LaTeX plugin and multiline chapter/section titles

[Kostafey]

LaTeX plugin can't see multiline sections.

Example:

\section{It is a very-very long text in the section name}
\label{sec : section1}

- ok, LaTeX plugin works

\section{It is a very-very
long text in the section name}
\label{sec : section1}

- error: LaTeX plugin can't see this section.