[ITB-1853] Extend the assign step to allow an assignment by value for container types (maps and lists)

Author: costas80

gitb-types-specs/src/main/resources/schema/gitb_tdl.xsd

@@ -345,6 +345,7 @@
 				<xsd:attribute name="append" type="xsd:boolean" default="false"/>
 				<xsd:attribute name="type" type="xsd:string" />
 				<xsd:attribute name="skipped" type="gitb:BooleanOrVariable"/>
+				<xsd:attribute name="byValue" type="xsd:boolean" default="false"/>
 			</xsd:extension>
 		</xsd:complexContent>
 	</xsd:complexType>