Collections tests
removes AddIf
adds comments
IEnumerableExtensions tests
IEnumerableExtension tests - split without clearEmpty
DateExtensions summary
removes DefaultDateFormat
DateExtensions - adds ToDayEnd
DateExtensions - adds ToIsoFormat
NormalizedFormat and CompactFormat tests
DateExtensions.ToIsoFormat - add DateTimeKind support and tests
DateExtensions - adds ToDayStart test
DateExtensions - adds ToDayEnd test
DateExtensions - adds ToMonthStart & ToMonthEnd tests
DecimalFormatExtensions - ToInvariantFormat
renames DecimalFormatExtensions to DecimalExtensions
adds ToCurrencyString test
adds ToCurrencyInputString test
DecimalExtensions - ToInvariantFormat test
DecimalExtensions - renames ToInvariantFormat to ToInvariantString
DoubleExtensions - renames ToInvariantString param
DoubleExtensions test