fixed shaded package name

[lbergelson]

Fixed the maven shade command so it produces a valid shaded package name. It was producing shaded.cloud-nio.* which is not a valid java package and causes compilation errors when trying to import those packages. This is problematic since the shaded packages are exposed in the API, so methods that exposed them were unusable by client code.

Shading now produces shading.cloud_nio.* which is valid

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[lbergelson]

@jean-philippe-martin Could you take a look at this?

[coveralls]

Changes Unknown when pulling 6173700 on lbergelson:master into ** on GoogleCloudPlatform:master**.

[jean-philippe-martin]

Looks good to me.

[garrettjonesgoogle]

@lbergelson , could you do the CLA dance?

[lbergelson]

@garrettjonesgoogle Sorry, I've been trying to talk to legal at the Broad. They've haven't responded to me yet. We have some sort of code sharing agreement already with google, but I'm not sure if they want me to sign the CLA or if there's some other agreement in place that takes precedent.

[garrettjonesgoogle]

@jean-philippe-martin this change is pretty trivial - you could just make a different change that accomplishes the same thing and avoid the whole CLA issue.

[garrettjonesgoogle]

Superseded by #1767