Update in crt_v2.sh, new docs and cleanup

[TheArqsz]

Hi @az7rb First and foremost, thank you for creating crt.sh! I've been using it in a few of my automated bounty environments, and it has proven to be useful. While the script itself might appear simple, it does an amazing job of consolidating and cleaning up the communication with crt.sh.

During my usage, I noticed a few minor areas where the script could be updated and cleaned up for improved readability and maintainability. I've gone through and made some adjustments.

I've also added comprehensive docstrings to all functions and the tool itself. My aim with this is to make the codebase more understandable and easier for future contributors to navigate and enhance. I actually used my own bashdog tool for this, which you can find here.

I hope these changes are beneficial for the project. Please let me know your thoughts, and I'm happy to make any further adjustments.