Fixed methods description

These methods were declared void but actually returns values. Added proper documentation.

htdocs/core/class/commonobject.class.php

@@ -2135,7 +2135,7 @@ abstract class CommonObject
      *	Add/Update all extra fields values for the current object.
      *  All data to describe values to insert are stored into $this->array_options=array('keyextrafield'=>'valueextrafieldtoadd')
      *
-     *  @return	void
+     *  @return int -1=error, O=did nothing, 1=OK
      */
     function insertExtraFields()
     {

htdocs/core/class/html.formcompany.class.php

@@ -509,7 +509,7 @@ class FormCompany
 	 *  @param  string		$htmlname       Name of HTML form
 	 * 	@param	array		$limitto		Disable answers that are not id in this array list
 	 *  @param	int			$forceid		This is to force another object id than object->id
-	 * 	@return	void
+	 * 	@return int The selected third party ID
 	 * 	TODO obsolete ?
 	 * 	cette fonction doit utiliser du javascript quoi qu'il en soit !
 	 * 	autant utiliser le système combobox sans rechargement de page non ?