Add descriptions for each of the 18 columns in the “Advanced Row” section

In the [Developing with ENgrid page, under the “Advanced Row” section](https://github.com/4site-interactive-studios/engrid-docs/blob/5117a9a1c5a34ed7d686c3c9580335f303232fe3/src/pages/docs/v2/developing-with-engrid.md?plain=1#L162), please add explanations for each of the 18 available columns (e.g., page-alert, content-header, body-headerOutside, etc.), describing their purpose and intended usage.