Add Bindings & initial taking away depreciated code

### Bindings
Added Bindings to tree_manager class
Added method for adding bindings
Added method for getting bindings

### Tests
Added 2 tests for the bindings methods created

### Depreciated Code
I don't think I did exactly what you wanted, but I just took out the warnings without removing the methods of the depreciated code. I received a failure in the tests when I attempted to remove this method in the select_manager.rb file:
~~~ruby
def insert values
~~~

The error I received was this:
~~~ruby
# Running:

.....................................F...............................................................

Finished in 0.146642s, 688.7522 runs/s, 791.0421 assertions/s.

  1) Failure:
select manager::insert#test_0001_uses the select FROM [test/test_select_manager.rb:446]:
--- expected
+++ actual
@@ -1 +1 @@
-"INSERT INTO \"users\" VALUES(NULL)"
+"INSERT INTO NULL VALUES(NULL)"
~~~

Should I be removing the depreciated methods, then try to fix this bug?