move approvals version of Java to own folder, provide alternative starting point and documentation

Java-Approvals/build.gradle

@@ -0,0 +1,22 @@
+plugins {
+    id 'java'
+}
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.6.2'
+    testImplementation 'org.junit.jupiter:junit-jupiter-params:5.6.2'
+    testImplementation 'org.junit.jupiter:junit-jupiter-engine:5.6.2'
+    testImplementation 'com.approvaltests:approvaltests:12.3.1'
+}
+
+group = 'com.gildedrose'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '1.8'
+
+test {
+    useJUnitPlatform()
+}