Add Mongo auto configuration

Spring Data Mongo is the only dependency so it doesn't
really need a new starter. Added a sample though.

spring-boot-samples/spring-boot-sample-data-mongo/pom.xml

@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<!-- Your own application should inherit from spring-boot-starter-parent -->
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-samples</artifactId>
+		<version>0.5.0.BUILD-SNAPSHOT</version>
+	</parent>
+	<artifactId>spring-boot-sample-data-mongo</artifactId>
+	<packaging>jar</packaging>
+	<properties>
+		<main.basedir>${basedir}/../..</main.basedir>
+	</properties>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.data</groupId>
+			<artifactId>spring-data-mongodb</artifactId>
+		</dependency>
+	</dependencies>
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+</project>