Adding Flag for removing stopwords

[leafoliage]

Description

This PR adds a flag --stopwords, which removes stopwords from abbreviation.

Fixes #33

Type of change

• [x] New feature (non-breaking change which adds functionality)
• [x] This change requires a documentation update

How Has This Been Tested?

I’ve created a test for the removeStopwords function.

• [x] Running existing tests
• [x] Created new tests

Checklist:

• [x] My code has been linted (make lint)
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] New and existing unit tests pass locally with my changes
• [x] I have rebased my branch to include the latest changes from master

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Legend

[dnnrly]

Thanks for this new feature @leafoliage - and apolgies for taking so long to merge it. As is tradition, if you do twitter then please let me know your handle and I will git you a follow. :smile:

[leafoliage]

@dnnrly Thank you too for approving this PR! Here's my twitter handle: leafoliage