edit_participant.php
form was filling in timestamp if none was provided, should show blank

participants-database.php
process_form()
"date_recorded" field was trying to save date string in wrong format, resulted in zeroing out the field...now properly saves in MySQL timestamp format
added "new record" admin feedback message
parse_date() now returns false if string is false: it was needlessly returning the currrent date

PDb_Init class:
initial database was not correct. Internal timestamps were not set as timestamp-type fields
also set readonly bit on timestamp fields

git-svn-id: https://plugins.svn.wordpress.org/participants-database/trunk@809427 b8457f37-d9ea-0310-8a92-e5e31aec5664