SpeeDRF pojo

This branch will adapt the speedrfmodel to a dtree.treemodel and use dtree.treemodel's tojava methods.

Using this branch, we will create a dtree.compressedTree every time we create a singlenoderf.tree and append it to the speedrfmodel.

The output pojo passes the 7 tests: R/tests/testdir_javapredict/runit_SRF_*