Revert "CATALINA_OPTS is a better place than JAVA_OPTS."

This reverts commit 88a25d40b0d3a0a7eb4990f327e1fbf23f1bc365.
CATALINA_OPTS is a better place than JAVA_OPTS.
The former is only used when actually starting the Tomcat instance.
JAVA_OPTS is also used to start JVMs that only interact with Tomcat (for example the JVM instance that is used to send the shutdown-message to a running Tomcat instance).
Those JVMs usually don't need so much memory, also if you specify a jmxport on JAVA_OPT you'll get an error (port in use) when tryng to stop the JVM.