interpreter

To run tests: Build: cmake --build build -j8

Test: ctest --test-dir build --output-on-failure

Trace Segmentation faults: valgrind --leak-check=full --track-origins=yes ./monkey

Adding support for a new Type:

1. Add its class in AST
2. inherit from main parent classes
3. implement virtual functions
4. implement class specific functions
5. write basic tests
6. create parser function
7. register the function
8. write more tests
9. enjoy a new feature in language