- added RockDateTime.FirstDayOfWeek to use when doing week calculations since Rock uses Monday as the first day of week
- added ConvertToEnumOrNull<T> as an Enum extension
- fixed up DateRangePicker so it renders its client id, style and class values
- added Date Range mode to SlidingDateRangePicker
- added "Round Values" to LiquidDashboardWidget which will round the Y values and sums to the nearest whole number
- SlidingDateRangePicker now calculates the DateRange for Last X/Current 'Week' using RockDateTime.FirstDayOfWeek (Monday)
- removed YAxisLabel from Chart tooltip since it is redundant information that they already know from the chart