Draft: More issue fixes

Updates:

• Now terminates if there's errors in more than 0.5% (modifiable) of the bins.
• Fixed issue with landscape plots (issue #25 (closed)).
• Implemented & tested a custom unit parser (issue #20).
• Removed most AUSAlib dependencies; we still have a few, see issue #20.
• Split some functions into two (issue #8 (closed)).
• Changed all function signatures to snake_case, as used in the standard library (issue #14 (closed)).
• Added disclaimer to printed chi2 values (issue #24 (closed)).