Do not combine title and first character of content.

Want to avoid false hits on the combination.
Added debugs

Trying to find source of junk appearing
in file content when tagging.
Updates to testing around tags.

Note that get_tags does not return the content of the tag line.
get_tags now behaves more like one would expect.

get_tags returns tags from tagline.
get_tags_from_string still looks for @tag style tags in a string.
Bugfix - don't add filename to start when tagging.
Bugfix: No need to insert filename when removing tags.
Added a test for finding a date in a filename.