[IMPROVEMENT] Improve documentation clarity and usage example

[hridyasadanand]

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• I have used CCExtractor just a couple of times.

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This pull request improves documentation clarity by:

• Removing an outdated Travis CI build badge from the README.
• Adding a simple command-line usage example to the documentation to help new users understand how to run CCExtractor.

These changes aim to reduce confusion for first-time users and contributors by keeping documentation accurate and more beginner-friendly.