Initial Commit only include kotlinx.datetime utils, others will follow.

NOTEs:

1. use .toEpochMilliseconds() to convert to Long values
2. ALWAYS store dates un UCT
3. for this demo I used pastXDaysUtc(days = 5).toEpochMilliseconds().relativeTimeSpanUtc() to get a Long TimeDate value
4. for this demo I used now() (kotlinx.datetime.Clock.System.now) for Instant

• Instant.dateTimePeriod()=PT0.000324000S
• nowToLongSystemDefault()=1700058378780
• currentMoment()=2023-11-15T14:26:18.780031Z
• getCurrentTimeInSeconds()=1700058378
• currentDayFormatted()=2023 NOVEMBER 15
• currentMomentUtc()=2023-11-15T14:26:18.780062Z
• nowToLongUtc()=1700058378780
• nextMonthUtc()=2023-12-01T00:00:00Z
• firstDayUtc()=2023-11-01T00:00:00Z
• lastDayUtc()=2023-11-30T00:00:00Z
• dateInUtc()=2023-11-15
• in30DaysUtc()=2023-12-15T14:26:18.780031Z
• inXDaysUtc(days = 20)=2023-12-05T14:26:18.780031Z
• past15DaysUtc()=2023-10-31T14:26:18.780031Z
• past60DaysUtc()=2023-09-16T14:26:18.780031Z
• pastXDaysUtc(days = 20)=2023-10-26T14:26:18.780031Z
• Long.relativeTimeSpanUtc()= 5 days ago

P.S. Request more Utilities if you need.