Add support for animated GIFs

Update ImageBanner to support animated GIFs. Animations rely on ANSI
cursor codes so don't work so well in an IDE. They do, however, work
when running the app from a terminal.

See also commit 47bc5e71ab

Closes gh-11118

spring-boot-samples/pom.xml

@@ -25,6 +25,7 @@
 		<module>spring-boot-sample-actuator-ui</module>
 		<module>spring-boot-sample-actuator-custom-security</module>
 		<module>spring-boot-sample-amqp</module>
+		<module>spring-boot-sample-animated-banner</module>
 		<module>spring-boot-sample-aop</module>
 		<module>spring-boot-sample-atmosphere</module>
 		<module>spring-boot-sample-batch</module>