Move spring-restdocs version to dependency management

Closes gh-3905

spring-boot-actuator-docs/pom.xml

@@ -51,7 +51,6 @@
 		<dependency>
 			<groupId>org.springframework.restdocs</groupId>
 			<artifactId>spring-restdocs</artifactId>
-			<version>1.0.0.M1</version>
 			<scope>provided</scope>
 		</dependency>
 	</dependencies>

spring-boot-parent/pom.xml

@@ -23,6 +23,7 @@
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 		<maven.version>3.1.1</maven.version>
+		<spring-restdocs.version>1.0.0.M1</spring-restdocs.version>
 	</properties>
 	<scm>
 		<url>http://github.com/spring-projects/spring-boot</url>
@@ -196,6 +197,11 @@
 				<artifactId>lombok</artifactId>
 				<version>1.12.6</version>
 			</dependency>
+			<dependency>
+				<groupId>org.springframework.restdocs</groupId>
+				<artifactId>spring-restdocs</artifactId>
+				<version>${spring-restdocs.version}</version>
+			</dependency>
 			<dependency>
 				<groupId>org.zeroturnaround</groupId>
 				<artifactId>zt-zip</artifactId>