By falling back to json verification and then using that contents, users
can use both base64 and raw json for the auth env variable.

This also introduces the first proper unit test, here's to an even
brighter future!

ComposerAuth: Handle non base64 contents

This makes it possible to reuse a brancher node that does not have any items in the logbook anymore, which typically happens on older Brancher nodes.

Fixes #185

Brancher: ping host before logbook poll

It doesn't make any sense to fail on brancher already being cancelled or
not existing.

These unit tests have been written for classes that required little to
no changes in the source files to be testable.

…celled

Brancher: Handle already cancelled error

Release notes:
  https://github.com/ByteInternet/hypernode-deploy-configuration/releases/tag/3.6.1

Add unit tests for basic classes

On the Hypernode platform, we have validate_timestamps enabled by
default, so we don't have to manually clear the opcache. People can
still enable this by configuring `after('deploy:symlink',
'cachetool:clear:opcache');`.

deps: Update deploy-configuration to 3.6.1

Cachetool: Don't run by default