prepare-ghcjs

It is currently "designed" for one user.

I compile it and run via cron, but the minimal will be:

1. git clone
2. stack ghci
3. use one of the following commands

    syncLts
    latest lts
    syncNightly
    latest nightly
    sync (ltsCfg {checkResolver = return "bla-123.456"})
    for resolver bla-123.456

the output should be in the archive directory.

This is very manual, In the ideal world all changes here should go to ghcjs/ghcjs or to upstream packages I upload my builds thus I have ghcjs-host entry in ~/.ssh/config

I still explore the design space. The operation on boot packages should be:

override_by_copy
copy_from_hackage
copy_from_boot
patch_hackage

some of them might generate new dependencies in boot.yaml

GHC 8

Building for GHC 8.0.2 still need some manual pathching, but for now

$ stack ghci
$> :set -XOverloadedStrings
$> sync (lts8Cfg {checkResolver = return "lts-8.21"})