Apply fixes for MAVEN-584 and MAVEN-574.

Thanks Rafal!!


git-svn-id: https://svn.apache.org/repos/asf/maven/maven-1/plugins/trunk@113668 13f79535-47bb-0310-9956-ffa450edef68

multiproject/plugin.properties

@@ -13,4 +13,7 @@ maven.multiproject.ignoreFailures=false
 # Valid values are: "aggregate" or "independent".
 maven.multiproject.navigation=aggregate
 
-maven.multiproject.type=jar
+maven.multiproject.type=jar
+
+# directory under target/docs where aggregated sites are copied to
+maven.multiproject.aggregateDir=multiproject/