Rewrite the OLCBP planner to use the new Digraph datastructures
- Remove all Graph adapters and use IDigraph<T> across the engine
- Refactor and the planner and rewrite most of its functionality to adher to the new IDigraph
- Fix most of compilation warnings by using the selective compilation warning level #pragma warning(*) macros

Signed-off-by: MHesham <mhesham.fcis@gmail.com>