Support for formula rendering in HTML export

<div class="row">
    <div
        id="xwikicontent"
        class="col-xs-12"
    >
        <p>
            Example usage of the
            &#123;&#123;mathjax}}
            macro:
        </p>
        <p>
            Normal Wiki text
            followed by a formula
        </p>
        <div class="xwiki-mathjax">
            \begin&#123;eqnarray} 1
            &amp; = &amp; a x + b
            y\label&#123;eq:first}
            \\ 0 &amp; = &amp; c x +
            d
            y\label&#123;eq:second}
            \end&#123;eqnarray}
        </div>
        <p>
            Solving equation
            <span
                class="xwiki-mathjax"
            >
                \ref&#123;eq:second}
            </span>
            for
            <span
                class="xwiki-mathjax"
            >
                x
            </span>
            and substituting back
            into equation
            <span
                class="xwiki-mathjax"
            >
                \ref&#123;eq:first}
            </span>
            yields
        </p>
        <div class="xwiki-mathjax">
            \begin&#123;equation} y
            =
            \frac&#123;c}&#123;cb-ad}
            \end&#123;equation}
        </div>
    </div>
</div>