Fixed file include ref
Removed unnecessary or deprecated tests
Namespace expanded; other updates & fixes.

Updated:
- Namespace updated
- NoFCalendar is immutable rather than abstract

Fixed:
- ISOCalendar is not exported from Dates.jl so cannot use in
FinMarkets.jl
- isboxingday() calendar argument specification corrected
- isanzacdayholiday() needed boolean operator
- calendar_sydney.jl -> calendars_sydney.jl
- Sydney holiday methods’ calendar type declarations
- Integer doesn’t have `value` field (ActActISDA years method)