Another attempt to fix unit test on ibm jvm.
Fixed serialization of AbstractMultiCauseException.
Switched back to using ':' a separator for source set display names, as using '.' looks too much like a source file name
Some tweaks to binary display names, so that they are similar to source set display names.
Some tweaks to compile/assemble task descriptions.
Fixed generic signature.
Added @Incubating and javadoc edit.