This includes a naive implementation of a module system where imported
files have their imports recursively handled, strips the module/import
AST nodes, and then evals everything into a flat environment using
namespace prefixes like "Module.function".
To encourage organizing code in a way that helps in understanding, I
have implemented the common idiom of requiring a `main` function. In
tricu and other functional languages, it is usually placed near the top
of the module. The evaluator gracefully handles the situation of passing
multiple files where the intermediary "library" files do not have main functions.
Adds CLI options for compiling to a Tree Calculus, AST, Ternary, and
ASCII tree view. Adds CLI command for attempted decoding of a compiled
result to Number/String/List.
Includes better error handling, additional tests, parsing and lexing
fixes to match the desired behavior defined by the new tests, and a very
basic REPL implementation.
