_idle(): s/error/abort; cleanup (see below)
_idle(): s/error/abort; cleanup (see below)

 * use abort on _all_ IDLE errors, so a failed IDLE (e.g. due to network
   outage) won't trigger a fatal error, as we can recover from that
 * add explanatory comments to _idle() - for maintainability
 * shorten error messages in _idle(), so `raise` doesn't span multiple
   lines

Andrwe/py3status,valdur55/py3status,Andrwe/py3status,valdur55/py3status,ultrabug/py3status,tobes/py3status,guiniol/py3status,valdur55/py3status,guiniol/py3status,ultrabug/py3status,tobes/py3status,ultrabug/py3status