The new definition of the bplustree now works with insertion
Finished proof for split_insert_normal.
Updated ValidBPlusTree to work with the new node-structure.
Updated proofs so they work with the new BPlusTree, and updated the assumptions of the split_leaf_cons proofs.
A bit of work on split_list'_preserves_lists, but it seems to be going the wrong way.
Added a possible proof for insert_leaf_cons_lt_overflow.
Removed extra argument for split_list_... Something
Added proof for insert_leaf_cons_gt_overflow.
Merge branch 'master' of github.com:nicolaidahl/BPlusTrees