Emacs: pulsar version 0.3.0

Pulsar is a small package that temporarily highlights the current line, either on demand or automatically after invoking a function that is present in a user-defined list. Watch the demo and consult the manual for the technicalities.

Below are the release notes.

Version 0.3.0 on 2022-04-08

Changed the source repository from GitLab to SourceHut: https://git.sr.ht/~protesilaos/pulsar. Use the mailing list to start a discussion, report a bug, send a patch, etc.: https://lists.sr.ht/~protesilaos/pulsar. The GitLab URL will serve as a mirror from now on (a GitHub mirror is still available and will remain that way).
Refined how Pulsar behaves in the case of the last line. Basically, when the last line cannot be highlighted we want to pulse the one right above. Thanks to JD Smith for fine-tuning this behaviour in merge request 1 over at the GitLab mirror: https://gitlab.com/protesilaos/pulsar/-/merge_requests/1 (exempt from the requirement to assign copyright to the Free Software Foundation as it is below the threshold).
Ensured that the Pulsar effect are limited to the current window when the buffer is displayed in multiple windows. This avoids the common problem of simultaneous highlights in multiple locations, which confuse rather than inform the user of where the point is. Thanks to Aymeric Agon-Rambosson for the contribution in merge request 2 over at the GitLab mirror: https://gitlab.com/protesilaos/pulsar/-/merge_requests/2. Aymeric has assigned copyright to the Free Software Foundation.
Wrote a buffer-local and a global minor mode that sets up Pulsar. This supersedes the old design which had a built-in assumption that the “pulse line” effect should always be global. Now the user has more flexibility. They may also disable Pulsar on demand. Note that pulsar still only triggers its effect for entries in the user option pulsar-pulse-functions. Thanks to Rudolf Adamkovič for the feedback in issue 9 over at the GitLab mirror: https://gitlab.com/protesilaos/pulsar/-/issues/9.
Implement the pulsar-highlight-dwim command. It is like the pulsar-highlight-line except it also understands regions, be they regular or rectangular. Thanks to Mark Barton for the feedback in issue 13 over at the GitLab mirror: https://gitlab.com/protesilaos/pulsar/-/issues/13.
Clarified some technical points in various doc strings and the manual, such as what is the pulsar-delay and the pulsar-iterations. Thanks to Rudolf Adamkovič for the feedback in issue 12 over at the GitLab mirror: https://gitlab.com/protesilaos/pulsar/-/issues/12.