Avoid compiling damlc twice

[aherrmann-da]

This only compiles damlc-bootstrap as a Haskell binary and damlc is a simple symlink with additional runfiles.

To that end this PR adds a small Bazel rule add_data that symlinks a binary (copy on Windows) and extends its runfiles. Ideally, we could achieve the same using sh_binary, however due to bazelbuild/bazel#11820 this would break some targets using damlc.

We now need to define damlc@ghci manually since it is no longer defined automatically. The manual definition was tested with

$ bazel run //:damlc@ghci --define ghci_data=True
> :main ide -d

The release tarball is not affected since package_app bundles the full binary.

To be sure I have tested the resulting HEAD SDK on Windows and Linux by following the quickstart-java/quickstart test steps defined in the relase test guide.

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[cocreature]

Very cool, thanks a lot!