* ghcjsHEAD: don’t just copy & replace, reuse same code
The HEAD file was just copied over and a few hashes replaced.
Most of these hashes were already function arguments anyway, so no reason to not
abstract over that.
* ghcjs/base: factor out stage1Packages & regenerate for HEAD
The stage1Packages have changed on ghcjs head, this adds the new list.
b399de2970