Botskeleton

better log handling
* FEATURE
* use botskeleton's new date rotated logs.
* pass arguments from re-exposed bottilities log helper correctly.

correct argument handling
* BUGFIX
* my recent attempts to allow keyword AND positional arguments in botskeleton while leaning
towards the keyword arguments was flawed.
you couldn't call the methods at all without positional arguments.
this fixes that,
handling arguments correctly.
there's even a nice-ish error message.
* birdsite needs a non-empty caption if you're doing captions at all.
I've resolved this by putting in a sensible default,
to be used if no caption is provided when uploading an image/images.

html unescaping
* BUGFIX
* both birdsite and mastodon batch reply would give HTML-encoded strings to the caller.
this runs html.unescape on the strings to turn things like > back into >.

dm manual fix
* BUGFIX
* birdsite dm was entirely broken without me noticing,
because birdsite changed the API and tweepy hasn't yet adapted.
fixed with a manual block similar to how caption upload is done.
* add another check when procesing error to record,
in case error can't be json dumped.

* DEV
* make _handle_caption_upload and _upload_caption "private" with the leading underscore.
* force keyword-only args in handle_error.
* have batch_reply handle target handle either with or without a leading "".

more error handling
* BUGFIX
* batch reply won't crash on a duplicate message on the birdsite output.

correct batch reply
* BUGFIX
* Batch reply for both birdsite and mastodon was broken.
* Fix birdsite reply to get the full message text correctly.
* Fix mastodon reply to get the correct target account or fail out.