1. Print out the length of the message and ask if it should be sent
2. If "Y" or ("y" or [RETURN]), send the message. Don't otherwise.
3. If `-f` is passed on the command-line, don't ask, just send.

Merging 'git.home/enhancements/22_post_to_more_than_one_service' into master as I've done enough -- it works.

Merging branch 'enhancements/23_post_to_mastodon' into enhancements/22_post_to_more_than_one_service as the work has been done

Merging 'enhancements/24_post_to_friendica' into enhancements/22_post_to_more_than_one_service as the work is done.

Merging branch 'enhancements/22_post_to_more_than_one_service' into enhancements/23_post_to_mastodon to bring it up-to-date with a bug-fix

Merging 'enhancements/22_post_to_more_than_one_service' into enhancements/24_post_to_friendica to encorporate a bug-fix

Fixes #17