optional data incorrectly parsed by function or task file_or_content

[abuxton]

Describe the Bug

https://github.com/puppetlabs/puppetlabs-peadm/blob/master/functions/file_or_content.pp
the variables are strongly typed as String, yet the input is Optional

both license and r10k value are opotional but last code refactor includes chanegs that expect the values to be set! this is undesirable in usage while demonstrating the module and or in mono builds as the supporting infrastructure is not always available these were previously captured in if statments!

https://github.com/puppetlabs/puppetlabs-peadm/blob/master/plans/action/install.pp#L106
https://github.com/puppetlabs/puppetlabs-peadm/blob/master/plans/action/install.pp#L109
https://github.com/puppetlabs/puppetlabs-peadm/blob/master/plans/action/install.pp#L133

Expected Behavior

it should work without optional data

Steps to Reproduce

Steps to reproduce the behavior:
run the task with out values for license or r10k key

Environment

Additional Context

2 possible fixes
update the function to allow undef Optional[String]
update the plan to re introduce if case statement

[bwilcox]

#66

Here's a fix...

[reidmv]

Merged #66