bump to version 2.52.3
Merge branch 'master' of github.com:globaleaks/GLBackend

* 'master' of github.com:globaleaks/GLBackend:
  bump to version 2.52.3
  fine tuning of login delay (was raising so much also to be unit tested)
  fixed a bug in mail notification sched
  bump to version 2.52.2

Conflicts:
	debian/changelog
	globaleaks/__init__.py
Add support for coveralls
Merge branch 'master' into devel

Conflicts:
	.travis.yml