#5 Lots of PHP and Smarty errors and warnings

[Don]

This is on a Gentoo system, using PHP 5.6.13 and Smarty 3.1.21

Here are a few examples:

Deprecated: mysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead in /var/www/localhost/home_inventory/htdocs/environment.php on line 26

Notice: Undefined property: Smarty::$configs in /usr/share/php/smarty/Smarty.class.php on line 763

Notice: Undefined property: Smarty::$cache in /usr/share/php/smarty/Smarty.class.php on line 763

Notice: Undefined index: action in /var/www/localhost/home_inventory/htdocs/editItem.php on line 13

Notice: Undefined index: action in /var/www/localhost/home_inventory/htdocs/editItem.php on line 13

Warning: date(): It is not safe to rely on the system's timezone settings. You are required to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /usr/share/php/smarty/plugins/function.html_select_date.php on line 59

Variations of this are loaded into the edit boxes:

Notice: Undefined index: ITM_Description in /var/www/localhost/home_inventory/smarty/templates_c/af616821240dce41b69eea77c4e1943f63a1931d.file.editItem.tpl.php on line 117

I have no meaningful PHP skill.