Implement line number anchor

[nishidayuya]

This pull-request includes following:

• Open path_to_coverage/index.html#<file_id>-L<linenumber> to display source code with scrolling to specified line number.
• Make source code line as hyperlink to path_to_coverage/index.html#<file_id>-L<linenumber>.

Closes #49

[nishidayuya]

Rebased from 7d1db36 (old master branch) to 3a30b47 (currently main branch)

This branch HEAD changed from 2d4a4aa to 07fb07d.

[nishidayuya]

Rebased from 3a30b47 (old main branch) to 5bc5798 (currently main branch)

This branch HEAD changed from 07fb07d to eecec23.

[joshuapinter]

This would be extremely helpful! Can we please get this reviewed and merged in?

The workflow of having to refresh the browser and scroll to the desired lines seems to be a common one.

Only thing that would make this better is the page auto refreshing when the coverage changes to reflect the coverage in real-time without any refreshes.

Thanks!

[joshuapinter]

@nishidayuya Mate, I just merged your branch into our fork and this is so helpful. Makes adding tests and refreshing the existing index.html browser tab so much faster. Thank you for doing this.

Anybody landing here looking for a solution, I suggest using @nishidayuya's fork until this gets merged into main, which doesn't look like it will happen anytime soon. I'm still waiting for a PR of my own to get merged in: #117.

[amatsuda]

This seems like a nice enhancement indeed. Thank you @jantman and @nishidayuya!