Further improvements once this round of tables is complete

[rdstern]

@Patowhiz is (I think) adding the updates to his tables sub-dialog for the next update. I list here partly for @N-thony some of the tables-related tasks that remain. They should only need work from Patrick in his more routine roles of supervising, trouble-shooting and testing.

a) Add the Table options `back into the 2/3/ Variable summarise dialog.
This is an important dialog that @Vitalis95 is just completing. It used to be just 2 variables. Now it produces (currently) exploratory 2 and 3-way tables of frequencies, and 2-way tables of summaries. They have only 1 variable (at most) across. It will, I hope, be easy to add the Table Options sub-dialog, when just a single table is produced. This can be done first. The dialog often produces multiple tables. Ideally that will also be possible, where formatting can be improved for all the tables in the same way? If that is challenging - that's typical of a challenge from menus - then we should explore whether it could be done via a script. @lilyclements is exploring loops in scripts.

b) Add the margins dialog to R-Instat, issue 9022, though I need to specify better, before this can start. We have outside margins already in the summary dialog, which uses the same ideas as the margins function, and was imaginative coding by David and Danny in the early days. (Note that the full margins of a 4 way table are a 3-way table, and margins get complicated for summaries, when they are not the same function as used in the summary. For example for daily rainfall data, we can use the sum to get monthly totals, but then may want to use the mean to get the margin over the years.)

c) I note the drop unused levels is now already just added into the summary tables dialog. That's a neat addition.

d) Consider which dialogs to include in the climatic menu and whether to adapt them, or use them as they stand. Maybe adapting them could provide a neat presentation table for summarised data, from the Climatic summary dialog?

e) Check the use of the Presentation dialog, with the Climatic > Check Data Missing and Picsa > Crops dialogs. They both produce data frames as output.

f) Explore the limitations of the Presentation dialog and include checks or remedies. This is the sort of thing @volloholic would have included automatically, but few programmers consider. I have avoided looking at this topic to focus on the important task of tables from summary data. But, when we have time, what happens when the cells of the data frame are of "interesting" types. They can be complex numbers, or lists, or long texts, or very long numbers, or even geometries. (For me the formatting of data frames has been an unexpected and welcome bonus, but unfortunately, it has, until recently been at the expense of formats for tables.

g) Add common options to the main dialogs for Use Table and Presentation. This is what R-Instat does. For simple use, just the main dialog should be all you need. The sub-dialog, then adds massive flexibility.

h) Add in facilites for multiple missing values in R-Instat. @volloholic keeps saying that's easy and I hope he is right!

i) What else?