Add TestData project containing Unicode UCD files

[GrabYourPitchforks]

This contains the Unicode data files that are needed by dotnet/runtime#328. I followed steps 1 - 3 in the README and verified that this package can be consumed by our test projects.

Open questions:

1. Do we really want to name this Private.CoreFx.TestUtilities.Unicode.TestData? It will eventually be consumed by several unit projects, including Private.CoreFx.TestUtilities.Unicode, System.Globalization.Tests, and System.Text.Encodings.Web.Tests. (I'll need to make a minor change to this and bump the version to 1.0.1 before that last project can consume it.)

2. Do we need THIRD-PARTY-NOTICES.TXT? These files are copied from https://www.unicode.org/Public/, and we have a similar notices file in the runtime repo.

[ViktorHofer]

Yes we need a THIRD-PARTY-NOTICES.TXT. Please see 2a90188 for an example.

Do we really want to name this Private.CoreFx.TestUtilities.Unicode.TestData?

You decide on the name :)

[GrabYourPitchforks]

@ViktorHofer I didn't even see that notices file under the project folder. Should I also throw this one under the new project folder (which I guess means it gets swept up as part of the nupkg?), or do we want to move it to the repo root?

[ViktorHofer]

I think we should move it to the repo root and include your notice. I think it being part of the package was a mistake.

[GrabYourPitchforks]

Ok, I'll fix it up when I'm back in the office.

[GrabYourPitchforks]

Changes in most recent iteration:

• Old THIRD-PARTY-NOTICES.TXT merged into new file at repo root.
• Bumped version of System.IO.Compression.TestData since I technically changed the contents of the package.
• Renamed CoreFx.Private.TestUtilities.Unicode.TestData to Microsoft.Private.UnicodeData.

[ViktorHofer]

What about Microsoft.Private.Runtime.UnicodeData to make the intent clear?

[ViktorHofer]

/azp run runtime-assets

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[ViktorHofer]

The repo is now ready. Feel free to merge after addressing my last comment :) I'm still not 100% sure about the package name. Looping in a few other folks who might be interested: @akoeplinger @jkotas

[GrabYourPitchforks]

System.Private.* works for me. :)