Added support for New Zealand

[badams]

Adding support for New Zealand national holidays.

[stelgenhof]

Thanks for the support of adding New Zealand! Looking forward to the final PR 👍

[badams]

Thanks @stelgenhof I saw your post on /r/php and liked the library, so I wanted to contribute to improve the coverage.

My plan is to finish off the national holidays for NZ, then I'll create a new PR for provincial holidays. If you want, and I have time I'll start another PR for Australia support later.

I'd appreciate if you could review what I've done so far and make sure I've not deviated from the goals of the project, I've added Mondayisation to all the applicable holidays

[stelgenhof]

Thanks @badams! Let me have a look later this week. I will then merge it with the base branch. I have set this as a milestone for the 1.3.0 version release :)

[badams]

Sounds good to me @stelgenhof 👍

[stelgenhof]

Wow! Nice list... Would it be possible to generate the dates rather than hardcoding them? Would be more sustainable I think :)

[badams]

@stelgenhof These lists are actually generated, I didn't write them by hand don't worry :)
My reasoning for hard coding them was that the code used to generate them seemed a bit too complex for unit tests, it resembled the calculation methods in the provider; to me it made sense to keep the tests as simple as possible.

But that's no problem I can use the code I generated the lists with instead.

[badams]

@stelgenhof does this look okay?

[stelgenhof]

Yes, looks great! BTW There have been some new commits after your created this PR, so might want to sync up your PR :)

[badams]

Ok I'll update the rest of the tests

[badams]

@stelgenhof I've adjusted all the tests as requested, let me know if anything else :)