Create php verification function(s) in tables class

[nate]

This would help with APIs to be able to use phpbms tables without having to work as hard at data integrity. Similarly, it would help to make the import routine in the next version a little more robust, so that the user has to think less about how their data might affect data integrity.

Ideally, it could run with regular table submits as well to be sort of a backup for the javascript verification as well. Possibly, just put it into the processAddEditPage function. Maybe let it return an array of errors and then check the count of the elements in this array to see if verification passes.

[brieb]

Initial implementation as of [470]