Produce debuginfo/dbgpkg RPM and Debian packages

[dagood]

The Microsoft approach of storing symbols in a symbol server and downloading them based on file info is unusual for Linux development. We should provide debug packages that contain symbols and install them adjacent to the corresponding binary to fit in better with the ecosystem.

Both native and managed symbols should be included.

• Debian package dbg/dbgsym packages: https://wiki.debian.org/DebugPackage
• RPM debuginfo packages: https://docs.fedoraproject.org/en-US/packaging-guidelines/Debuginfo/
  • Note that source is normally included, but since Core-Setup doesn't clone CoreCLR/CoreFX in order to build, this may not be realistically achievable in the Microsoft-built debuginfo package.

Ideally this functionality can be included in shared tooling and apply to ASP.NET Core and the .NET Core SDK, but no such shared tooling currently exists. (Once it does, this issue may belong in dotnet/arcade.)

/cc @sdmaclea @dleeapho