Add additional logic for included files in package

[yeazelm]

Homebrew can't reuse a Keg exported from this tool because of the way the rsync copies the files and dereferences the symlinks. This still produces a working package, but Homebrew complains about it. This commit adds in the additional logic needed to produce a tree in the package that let's Homebrew reference and use the Keg as if Homebrew had installed the Keg rather than via a pkg. The key value to this change is that the resulting package can be used to "bootstrap" the package via a package and then let Homebrew maintain it after the fact.