Fixes for php7.4 - travis

.travis.yml

@@ -50,6 +50,7 @@ install:
 
 services:
   - mysql
+  - xvfb
   
 before_script:
   # copy configuration files

app/DataMapper/ClientSettings.php

@@ -53,7 +53,7 @@ class ClientSettings extends BaseSettings
 	 */
 	public $industry_id;
 	public $size_id;
-	public $invoice_email_list;	
+	public $invoice_email_list;	//default comma separated list of contacts to email
 
 	/**
 	 * Cast object values and return entire class