Update maven prerequisite

Closes gh-3614

pom.xml

@@ -44,7 +44,7 @@
 		</developer>
 	</developers>
 	<prerequisites>
-		<maven>3.0.0</maven>
+		<maven>3.2.1</maven>
 	</prerequisites>
 	<properties>
 		<main.basedir>${basedir}</main.basedir>

spring-boot-dependencies/pom.xml

@@ -159,7 +159,7 @@
 		<wsdl4j.version>1.6.3</wsdl4j.version>
 	</properties>
 	<prerequisites>
-		<maven>3.0.2</maven>
+		<maven>3.2.1</maven>
 	</prerequisites>
 	<dependencyManagement>
 		<dependencies>

spring-boot-parent/pom.xml

@@ -24,9 +24,6 @@
 		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 		<maven.version>3.1.1</maven.version>
 	</properties>
-	<prerequisites>
-		<maven>3.0.2</maven>
-	</prerequisites>
 	<scm>
 		<url>http://github.com/spring-projects/spring-boot</url>
 		<connection>scm:git:git://github.com/spring-projects/spring-boot.git</connection>