Refactor packages to enable excluding locales

[clairernovotny]

This PR tracks #59

[MehdiK]

Looks good. Thanks @onovotny.

[MehdiK]

I am just a bit unsure about Humanizer.all name although I'm not sure what else I would call it!

[MehdiK]

I am just thinking that when/if there are other packages as part of the library, then all implies everything while we just mean all the resources.

[clairernovotny]

So right now, I have Humanizer as the meta-package that pull in every Locale and Humanizer.Core. Essentially, it preserves current behavior.

For people that don't want all locales, they can just directly install the Humanizer.Core package.

Nothing has changed with the dll's or their names, it's all just packaging.

[MehdiK]

Nice 👍

[clairernovotny]

Testing on UWP has turned up an error installing the localized packages...a false error I believe. @emgarten, can you please assist (email with details should be in your inbox)

[clairernovotny]

@emgarten: easy repro, check out the features/integration branch and try to add Humanizer.Core.ar to it via NuGet (selecting the CI feed). You'll see an error about it not being compatible with a UWP app. If you add to the project.json manually, you get that error on build instead.

[clairernovotny]

There's a fix for this but it's dependent on this PR being merged in (and shipped to the public):
NuGet/NuGet.Client#95