Extended lookup unit test of evaluator to look for a function,
which is failing at the moment.
Simplifies evaluate function a lot and also fixing bugs.
Removed empty () on lambdas.
:lipstick: renamed test function in eval test.
Fixed wrong error message in lambda.
Added lots of logging in evaluator and some builtin stuff.
Moved some implementation of Environment to new file environment.cpp
Implemented setter for SchemeFunction.
Added unit test for evaluating clojures.