Fix NullPointerException for null Instant in JSON serialization

Bug Fixes

Fixed NullPointerException in JsonUtils.InstantAdapter when serializing objects with null Instant fields via JsonApprovals.verifyAsJson(). The adapter now correctly writes a JSON null value, matching the existing behavior of LocalDateTimeAdapter. (#765, #766)

verify(java.nio.file.Path)

26.7.0

. d reformatted code and updated markdown snippets

Better help message for DateScrubber

26.6.1

. d reformatted code and updated markdown snippets

Fixed name of ExtensionFileFilter class

Fixed a speling mistake

DateScrubber supports more dates

This addresses the requests from @thomo (timezone offsets) and @thunderhook (LocalDateTime without Z).

Added the ability to add known text file extensions

Closes #337

Headers and Labels for Combination and Pairwise Approvals

CombinationApprovals.verifyAllCombinations(
    new Labels().withHeader("processCall(String, Int)").withLabels("number", "letter"), this::processCall,
    new Integer[]{1, 2, 3, 4, 5}, new String[]{"a", "b", "c", "d"});

will produce

processCall(String, Int)


[number: 1, letter: a] => [1, a] 
[number: 1, letter: b] => [1, b] 
[number: 1, letter: c] => [1, c] 
[number: 2, letter: a] => [2, a] 
...

closes #194
closes #200

Support the difference in kotlin packages vs directory structure

closes #352

PackageSettings allows private constructor

fixes #370

FirstWorkingReporter & DateScrubber improvements

FirstWorkingReporter now has toString implementation (#140 )
DateScrubber now accepts SimpleDateFormat (closes #165 )