Add Laravel version selector and format results

[jakebathman]

Thanks a ton for this workflow!

Overview

This PR adds a few things:

• An optional Laravel version at the beginning of the input (e.g. ld 5.1 helpers str) that replaces branch
• Formatting the results to only return unique URL results and show all available subheadings (h2,h3,h4)

The formatting won't fix #2 for minimal themes, but you might just permanently move h2 to the title and leave h3 and h4 for the subtitle.

Screenshots

Subtitles for context

Laravel version

[tillkruss]

I tackled duplicates in 1baa127 and h3 and h4 support in cff4527.

Feel free to submit to version shortcut separately.