Debug and Compiler Efficiency

This release adds the bsk debug command to the CLI. Running this will generate a post-parse tree of all scripts.
The output debug.txt file is useful for bug reports (or for advanced users tracing parse errors.)

The stream-based compiler has also been made significantly more efficient: rather than reading the entire file into memory, it will be read line-by-line and each line will be discarded once it has passed through the compiler.
This will make parsing large scripts significantly more efficient.

Jupiter has been added as a new dependency, for its lazy-iterable capabilities.

Full Changelog: 1.0.15...1.0.16