Polish cache sample

Update single cache sample with all supported cache providers. Add README
to shortly explain how to get started with them.

See gh-2633

spring-boot-samples/spring-boot-sample-cache/src/main/resources/application-override.properties

@@ -1 +0,0 @@
-spring.cache.config=/cache/ehcache-override.xml

spring-boot-samples/spring-boot-sample-cache/src/main/resources/application.properties

@@ -0,0 +1,19 @@
+
+
+#
+# Infinispan configuration file location.
+#
+#spring.cache.infinispan.config=infinispan.xml
+
+
+#
+# JCache configuration (example with hazelcast).
+#
+#spring.cache.type=jcache
+#spring.cache.jcache.config=hazelcast.xml
+
+
+#
+# Guava configuration
+#
+#spring.cache.guava.spec=maximumSize=200,expireAfterAccess=600s

spring-boot-samples/spring-boot-sample-cache/src/main/resources/cache/ehcache-override.xml

@@ -1,8 +0,0 @@
-<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:noNamespaceSchemaLocation="ehcache.xsd" updateCheck="true" monitoring="autodetect"
-         dynamicConfig="true">
-	<cache name="countries"
-	       maxBytesLocalHeap="50m"
-	       timeToLiveSeconds="100">
-	</cache>
-</ehcache>

spring-boot-samples/spring-boot-sample-cache/src/main/resources/ehcache.xml

@@ -1,8 +1,7 @@
 <ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:noNamespaceSchemaLocation="ehcache.xsd" updateCheck="true" monitoring="autodetect"
-         dynamicConfig="true">
+		 xsi:noNamespaceSchemaLocation="ehcache.xsd">
 	<cache name="countries"
-	       maxBytesLocalHeap="50m"
-	       timeToLiveSeconds="100">
+		   maxEntriesLocalHeap="200"
+		   timeToLiveSeconds="600">
 	</cache>
 </ehcache>

spring-boot-samples/spring-boot-sample-cache/src/main/resources/hazelcast.xml

@@ -0,0 +1,17 @@
+<hazelcast xsi:schemaLocation="http://www.hazelcast.com/schema/config hazelcast-config-3.4.xsd"
+		   xmlns="http://www.hazelcast.com/schema/config"
+		   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+
+	<map name="countries">
+		<time-to-live-seconds>600</time-to-live-seconds>
+		<max-size>200</max-size>
+	</map>
+
+	<cache name="countries">
+		<eviction size="200"/>
+
+		<statistics-enabled>true</statistics-enabled>
+		<management-enabled>true</management-enabled>
+	</cache>
+
+</hazelcast>

spring-boot-samples/spring-boot-sample-cache/src/main/resources/infinispan.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<infinispan xmlns="urn:infinispan:config:7.2">
+
+	<cache-container default-cache="default">
+		<local-cache name="countries">
+			<eviction max-entries="200"/>
+			<expiration lifespan="600000"/>
+		</local-cache>
+	</cache-container>
+
+</infinispan>