Rework the replacements flag

[CosmicHorrorDev]

Fixes #105

The replacements flag was added since the last release, but there were some issues I wanted to resolve before actually releasing it. Notably this:

• Reworks the whole CLI aspect
  • You can now also use the long flag --max-replacements <LIMIT>
  • Directly exposes that 0 indicates unlimited replacements
• Honors the number of replacements even when using --preview
• Adds a basic array of tests, so that the behavior is at least decently stable going forward