PLT-372 - Rename holiday calendar

HolidayCalendar makes more sense wrt the embedded constants
PLT-372 - Enhance holiday calendar

Add hasNoHolidays()
Fix bug when no holidays
Better toString()
PLT-407 - Add business day adjustment

Combines business day convention and calendar
PLT-407 - Add period adjustment

Combines a number of days and holiday calendar
Optional final business day adjustment
Javadoc and switch off doclint