IPF 4.0

[Christian Ohr]

Hi guys,

during the past months I stabilized and updated the 184-branch of IPF to build and run with 

• Java 11 (no, it does not work with Java 8 anymore)
• Camel 3.1.0
• Groovy 3.0.2

and a lot of other updates to dependent libraries, particularly related to Web Services and XML stuff.

The branch regularly builds on Travis with both openjdk11 and openjdk13 (though, at times it hits the max build time)

It does not yet make active use of the Java module system introduced with Java 9, i.e. everything ends up in the default module so far.

IPF 4.0 will not be fully backwards-compatible (although there are hardly any changes on the "Camel Route" abstraction level), so I took the chance and removed a bunch of deprecated classes and methods, too.

 My proposal to move on would be to:

* release 3.7.0 some time soon (maybe around the Connect-a-thon, if it actually takes place) and create a 3.7 branch

* convert 184-branch to master and publish a technical tag/milestone afterwards, so users can have a try.

* retire the 3.6 branch

We probably need maintain the 3.7 branch for quite a while for everyone who is stuck to Java 8, but we can independently carry on with 4.0.

More ideas or objections?

cheers

Christian

[Nimish Telang]

Would be good to have this. Module support shouldn't be a blocker, since most things don't support "real" modules. Just being able to run on newer java versions is good enough.