added documentation for rbcs-servlet

switched Docker images to serial GC

rbcs-servlet/README.md

@@ -0,0 +1,28 @@
+## How to run
+
+```bash
+gradlew dockerBuildImage
+```
+ then in this directory run
+```bash
+docker run --rm -p 127.0.0.1:8080:8080 -m 1G --name tomcat -v $(pwd)/conf/server.xml:/usr/local/tomcat/conf/server.xml gitea.woggioni.net/woggioni/rbcs/servlet:latest
+```
+
+you can call the servlet cache with this RBCS client profile
+```xml
+    <profile name="servlet" base-url="http://127.0.0.1:8080/rbcs-servlet/cache/" max-connections="100" enable-compression="false">
+    	<no-auth/>
+    	<connection
+	        idle-timeout="PT5S"
+	        read-idle-timeout="PT10S"
+	        write-idle-timeout="PT10S"
+	        read-timeout="PT5S"
+	        write-timeout="PT5S"/>
+        <retry-policy max-attempts="10" initial-delay="PT1S" exp="1.2"/>
+    </profile>
+```
+
+## Notes
+
+The servlet implementation has an in memory cache whose maximum
+size is hardcoded to 0x8000000 bytes (around 134 MB)