participants-database.php:
print_record_edit_form() method now loks for an in id the $_SESSION array, to facilitate multi-page forms
in process_page_request() signup submissions are now redirected to the "thanks page" if it has been specified in the shortcode: for multi[-page form support
admin edit form redirects edited for more compact code

pdb-record-default.php
pdb-signup-default.php
adapted for classed tbody elements containing groups

PDb_List class:
logic to prevent shortcode "action" attribute from affecting the search form action unless the module is "search"

PDb_Shortcode class:
added "action" shortcode attribute
added template_basename() method to show the template file name and it's parent directory in the comments
"action" shortcode attribute now sets the submission_page value

PDb_Signup page
added action attribute processing

PDb_Template class
many changes to class logic using the $values property
added $values property to hold raw values
added print_field_prop() method
added linking functionality: print_with_link()

git-svn-id: https://plugins.svn.wordpress.org/participants-database/trunk@813500 b8457f37-d9ea-0310-8a92-e5e31aec5664