Use proper h1 heading for blog entrys instead of h4

The titles in the blog app (https://<connections-hostname>/blogs/) uses a h4 heading, as you can see here:

<td class="lotusFirstCell entryContentContainerTD blogsWrapText"><a name="xyz" id="xyz"></a>
    <h4>
        <a id="entry-abc123:link:entries" href="https://link-to-blog-entry class="bidiAware">My Blog Title</a>
    </h4>
    <!-- ... --->
</td>

It doesn't seem to be good choice, since h4 is relatively small and h1-h3 can be used in blogposts. As a result, we have sub-headlines in the blog, which are bigger than the main blog entry headline itself.

To improve this, the usage of a higher heading-type would be better. Additional we could set a css class for the headline, which make custom styling easier. Currently the blog content is nested inside the headline-container, which make it impossible to simply re-formatting blog headlines since all styling affects the blog content itself, too.

With html code like this:

<td class="lotusFirstCell entryContentContainerTD blogsWrapText"><a name="xyz" id="xyz"></a>
    <h4 class="lotusBlogHeadline">
        <a id="entry-abc123:link:entries" href="https://link-to-blog-entry class="bidiAware">My Blog Title</a>
    </h4>
    <!-- ... --->
</td>

we simply could style lotusBlogHeadline and avode side-effects.