Update samples to make them compatible with Java 7

The main project supports Java 7 or later, but, prior to this commit,
the Spring HATEOAS sample required Java 8. This commit updates updates
the Spring HATEOAS sample to make it compatible with Java 7 and
updates the build configuration of both samples to specify Java 7.

Closes gh-51

samples/rest-notes-spring-data-rest/.settings/org.eclipse.jdt.core.prefs

@@ -1,14 +1,14 @@
 eclipse.preferences.version=1
 org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
-org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.8
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=1.7
 org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
-org.eclipse.jdt.core.compiler.compliance=1.8
+org.eclipse.jdt.core.compiler.compliance=1.7
 org.eclipse.jdt.core.compiler.debug.lineNumber=generate
 org.eclipse.jdt.core.compiler.debug.localVariable=generate
 org.eclipse.jdt.core.compiler.debug.sourceFile=generate
 org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
 org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
-org.eclipse.jdt.core.compiler.source=1.8
+org.eclipse.jdt.core.compiler.source=1.7
 org.eclipse.jdt.core.formatter.align_type_members_on_columns=false
 org.eclipse.jdt.core.formatter.alignment_for_arguments_in_allocation_expression=16
 org.eclipse.jdt.core.formatter.alignment_for_arguments_in_annotation=0

samples/rest-notes-spring-data-rest/build.gradle

@@ -23,6 +23,9 @@ repositories {
 
 group = 'com.example'
 
+sourceCompatibility = 1.7
+targetCompatibility = 1.7
+
 dependencies {
 	compile 'org.springframework.boot:spring-boot-starter-data-rest'
 	compile 'org.springframework.boot:spring-boot-starter-data-jpa'

samples/rest-notes-spring-data-rest/pom.xml

@@ -17,7 +17,7 @@
 
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<java.version>1.8</java.version>
+		<java.version>1.7</java.version>
 	</properties>
 
 	<dependencies>