Restore compatible insync? behaviour for matching arrays.

Prior to the start of these cleanups, when matching the entire array rather
than part of it, we accepted the situation where the is array - what the
provider returned - matched one of two arrays:

One, if it matched as-is the should array, which is what the resource is
configured to be delivering.

Two, if it matched the should array after every value in it was transformed
via to_s, into a string.

Preserving this does mean that the property_matches? method is no longer
used for comparison when array_matching :all is in force - because it
internally handles the value comparisons, we can't expose the logic that
refuses to match anything but the entire array to it.

Signed-off-by: Daniel Pittman <daniel@puppetlabs.com>