Scripts should login after initialisation

The following scripts unnecessarily login early in their main() block
or in the bot __init__, which may cause the bot to sleep, or raise an
exception.

Two instances of that, which have resulted in 'red' travis-ci builds
are the category and touch scripts:

https://travis-ci.org/wikimedia/pywikibot-core/jobs/32012605
https://travis-ci.org/wikimedia/pywikibot-core/jobs/31955520

Change-Id: I63e1699a4b70dde161c0430beaaa5ed0b44093cb
Merge "Scripts should login after initialisation"