During testing it was discovered that the `first-result' procedure
throws an exception, which left the database in a somewhat
inconsistent state, the bookmark had been added, but (at least one of)
the tags weren't added. This should make it all succeed or all fail.
* Add parsing of command line arguments, if the first argument starts
with "http://" assume it's a new bookmark and save it to the
database.
* Add adding bookmarks to the database.
* linkwave.scm (string-no-null): Only try to remove the final null
byte if the string is longer than 0 characters and only if the last
character _is_ a null character.
