Long link names cause horizontal overflow

[anschmieg]

Describe the bug
When a link has a long title like

some extremely long name of a publication or site or whatever, just click it anyway

LaTeX does not add breaks in between. Note that I only tried this for the moderncv theme, but it may be applicable to the others as well.

Possible fix
To circumvent this, i changed the definition of \href in Header.j2.tex to the following. This uses the parbox environment instead of mbox.

% New command for external links:
\renewcommand{\href}[2]{
  \hrefWithoutArrow{#1}{
    \parbox[t]{\linewidth}{
      \color{color1}
      \allowbreak #2
      \raisebox{.15ex}{
        \footnotesize 
        \faExternalLink*
      }
    }
  }
}

Sorry that I didn't just create a pull request, I've never done that before and didn't want to figure it out right now.