Consider adding support for caption or title for table elements

At the current time, QDoc does not seem to directly support any form of title/caption for table elements generated by the \table command.

This was a small issue, for example, during the conversion of the Froglogic's documentation set, where tables' titles/captions were, in the end, removed as not supported.

While a relatively low issue, as the appearance of a table can usually be preceded by a text explaining its presence in the documentation, the easiness of reading a table on its own may be increased by binding a small title/caption to it.

We might, hence, want to consider extending the \caption command to work with tables, modifying a \table directly to support a title/caption or a different approach altogether.