whats, updated for live scripts

Expanded original whats to include live scripts. Original summary: "Duplicates the output of Matlab function WHAT, with clickable links."

I edited the original file, with verbose comments, to expand the functionality to ".mlx" (live script) files.

The original whats function by Matt Fig, at https://www.mathworks.com/matlabcentral/fileexchange/20615-whats was last updated in 2008. Since then, live scripts have been introduced in Matlab, yet these files are not supported by the original function.

Let me know if you encounter any issues, as this was tested and made in R2021b, but I expect backwards functionality.

Contact: Find me on discord, username #Willingo3404. I am frequently in the matlab discord channel.

Potential future improvements:

1) Enable an option to list the subfolders and let the user click into the subfolder via dir function.

2) Enable list of all files in all subfolders via genpath function.

3) Separate out ".m" file listings into functions and non-functions.

4) Add more file type functionalities