Added Italian localisation and tests

Added date and time resources, collection formatter, number-to-words converters (cardinal and ordinal), ordinalizer.
We're just figuring out what to add in release_notes.md
Looking at it, it seems to me that most *important* bits of processing here are `Take`, `Skip` and `Join`. They all work with and return enumerables: of course, at run time also arrays implement enumerables. Now, it is not clear to me why in this method one should favour conversion to array, instead of just working with the input enumerable and forget about array altogether. At the moment, I'd go with the latter.