Fix warning on CiviCRM Group Roles-List Association Rules page and fix invalid insert query for CiviCRM Member Roles add rule funtion

civicrm_group_roles_show_rules in civicrm_group_roles.module was invoking civicrm_group_get($params) without defining the $params value. This caused an invalid attribute warning.

civicrm_member_roles civicrm_member_roles_add_rule_form_submit() function's $add_rule was passing an empty string for the rule_id (which is an auto-increment integer field). This resulted in fatal db insert error.