several css changes affecting the admin section due to change in admin theme in WP 3.8:
	edit_participant.php
	manage_fields.php
	pdb-admin-global.php
	pdb-admin.css

participants-database.php
added $session property
$plugin_options array is now filled with default values where there are no saved values
WP_Session class now handles all $_SESSION values
default timezone is now set using date_default_timezone_set()

PDb_Base class
handling of admin messages using WP_Session

PDbCAPTCHA class
using WP_Session to hold captcha values

PDb_List_Admin class
edit JS for better class toggling to arm the delete button

PDb_Settings class
new method to provide array of default values
eliminated empty value in retrieve identifier preference selector

PDb_Shortcode class
adapted to use WP_Session to save the shortcode atts

PDb_Signup class
adapted to use WP_Session
additional error messages added tor email debugging
'phpmailer_init' filter used to set a text body for HTML emails

updates to readme.txt

xnau_FormValidation class
is_empty() method now uses simple strict empty string test.

added Norwegian translation

git-svn-id: https://plugins.svn.wordpress.org/participants-database/trunk@821721 b8457f37-d9ea-0310-8a92-e5e31aec5664