Some parameters appear in groups rather than one per row

[davidbenncsiro]

In particular:

• bathy, depfile
• nx, ny
• cf, cfsand, cfreef
• fw, fwsand, fwreef
• x,y

Separating these into distinct rows will make parameters in the user manual completely machine readable.

This case is more complicated than those above but the same approach applies:

                  <td>drydzmax=1.0, wetdzmax=2.0</td>
                  <td>1.0, 2.0</td>
                  <td>Wet/dry max slope in avalanching model</td>

could become:

                  <td>drydzmax</td>
                  <td>1.0</td>
                  <td>Dry max slope in avalanching model</td>
                  <td>wetdzmax</td>
                  <td>2.0</td>
                  <td>Wet max slope in avalanching model</td>