Custom affinities and tolerations

[Jancis]

Allows definition of custom node and pod affinities, along with tolerations.

• Current drupal affinities moved from drupal template to values
• Current tolerations, created by inverse nodeSelector rules are kept, provides backwards compatibility with current nodeSelector rules
• Removes empty resources sections when no value present, instead of setting them to {}

Testing done with helm unittest and manually, by defining php.nodeSelector, php.tolerations, php.affinity, php.cron.nodeSelector, php.cron.tolerations, and php.cron.affinity values in various combinations, confirming expected output with helm template command.