Finished the Turtle state, interpretation, and draw models.

Signed-off-by: Peter Zastoupil <peterzastoupil@gmail.com>
Restructured the model packages to separate the interpreter and turtle
models effectively

Signed-off-by: Peter Zastoupil <peterzastoupil@gmail.com>
Finished the initial pattern-matching-model for the expression language
used in L-System definitions
 
Signed-off-by: Peter Zastoupil <peterzastoupil@gmail.com>
Cleaned up some glitchy auto-imports in the Turtle class

Signed-off-by: Peter Zastoupil <peterzastoupil@gmail.com>