Add support for danish locale

[michaelkrog]

What problem does this feature solve?

The lack of danish language in the components.

What does the proposed API look like?

I expect the API to be consistent with implementation of other locales.

[fisherspy]

Hi, @michaelkrog , currently there is a narrow vocabulary in nine components locale files, so it is easy to add a new language locale. However, none of us know danish, Would you like to create a PR?

[michaelkrog]

Gladly @fisherspy.

However, as I understand the codebase, it needs to be added to ant-design-mobile first, right?
I created a PR for Danish in that here: ant-design/ant-design-mobile#2962

Awaiting it to be merged in.

EDIT
Okay. I see now that I may have misunderstood the dependency on ant-design-mobile. I'll give it another try.

[fisherspy]

@michaelkrog you don't need to add it to ant-design-mobile, it's a react implementation. you just need to create a PR here. But the react team would be happy to accept your PR.

[fisherspy]

#115

[fisherspy]

@michaelkrog 0.9.9 is out, Danish is now supported, thanks to you!