(MAINT) Mergeback 0.5.1 release

Prior to this commit the DSC base provider would
occasionally need to send an empty array as a
defined property to Invoke-DscResource. However,
the CIM instance on the other end may not be able
to appropriately cast from an empty array to, say
a [String[]] type; this would cause the run to
fail. Furthermore, the provider did not have a way
to distinguish between an *absent* setting and an
*empty* one. Ruby does not treat empty arrays and
nil as the same, even though PowerShell can/does.

This commit adds a special handler for munging the
data returned from a get invocation, ensuring that
if a propertys value is nil AND the property was
used for the query AND the resource expects an
array, THEN it will set the result to the manifest
value or an empty array.

It also strongly types any empty arrays being sent
to Invoke-DscResource, as this prevents the casting
problem by making the array type casting  explicit
instead of merely implicit.

- Resolves #55

The move from master -> main broke CI.

…arrays

(GH-55) Handle intentionally empty arrays

Prior to this commit the dsc_base_provider could not handle
DateTime objects from Puppet, having no useful way to format
them for PowerShell nor read them back from a Get result.

This commit adds some minor handling to ensure that any
datetimes are cast appropriately in the param hash and can
be parsed by Puppet if returned.

- Fixes #57

(GH-57) Handle datetimes in dsc

Prior to this commit the DSC Base provider inherited from
the Resource APIs Simple Provider. This brought with it a
limitation in the type definition, requiring all of the
generated DSC types to have the ensure attribute. This
led to the confusion in puppetlabs/Puppet.Dsc#72 as well
as necessitated the filing of puppetlabs/Puppet.Dsc#74
to improve the UX.

This commit removes the dependence on the Simple Provider
and instead copies over the code from it - namely, the
set method - and modifies it slightly for brevity.

This change sets up a few things:

1. The collapse of the ensure and dsc_ensure attributes.
   Once merged, the ensure attribute becomes redundant;
   the provider no longer needs to care about it and it
   can be removed from both generation and the provider.
2. The dropping of the simple_get_filter from puppetized
   DSC Resource type definitions. The feature is made
   redundant in this commit and no longer used.
3. Refactoring of this provider for clarity. Now that all
   of the required code for this provider lives in this
   gem we can look to refactor some of the helpers out and
   clean things up a little.

- Resolves #59
- Unblocks puppetlabs/Puppet.Dsc#74

(GH-59) Refactor away from Simple Provider

This commit removes the special handling for the ensure keyword
from the dsc base provider to facillitate the collapse of the
ensure and dsc_ensure keywords.

- Relates to puppetlabs/Puppet.Dsc#74

(GH-74) Remove special handling for ensure in the dsc base provider

This commit removes parameters from the return hash
in invoke_get_method of the dsc base provider and
also removes the redundant handling for the
PSDSCRunAsCredential property, which is always a
parameter.

- Related to puppetlabs/Puppet.Dsc#81

…ters

(GH-81) Handle parameters in the dsc base provider

(MAINT) Prep for 0.6.0 release