Forms info: Recent changes

There have been some major changes in the system:

1. The database structure has been re-arranged. The old database format and the new one are somewhat incompatible.
2. The db query system has been optimised somewhat. I'm still learning to use PostgreSQL... :)
3. Form editing has many new features. These are documented in detail at 04_Modifying and 03_Results. New features include:
   1. Duplicating forms.
   2. Inserting questions into the middle of the form.
   3. Number ranges are now superceded by the more flexible compact multichoices.
   4. Long multichoices have numerical summary information.
   5. Labels.
   6. POST instead of GET so that browsers know the queries have side-effects.
4. Question numbers are no longer printed, they are only used to tell the order of the questions. Instead, questions are automatically numbered from 1 upwards in the form. These numbers have nothing to do with question numbers.
5. There is the possibility of giving your e-mail address when creating a new form.
6. POST instead of GET when collecting answers.
7. The result side has some new features. These are explained in 03_Results. They include:
   1. Multiple choice questions and number range questions are now basically the same thing, so both kinds of summary information are printed for both.
   2. There is a link to print all the results of a form as a table. This script can be very slow on large amounts of data.