Hello all,

Attached is a preliminary patch for fixing "the package-initialize
problem" (see [1] [2] [3]) by adding an early init file. Feedback
welcome. In particular,

- do we want to try to factor out some common logic in loading the
  early init file versus the regular init file?
- have I broken anything in moving the check for an invalid username
  earlier in startup.el? what about moving package-initialize earlier?
- should `early-init-file' be defined in C?
- did I miss any documentation fixes?
- have I broken any style guidelines for the repository?

Additional question: if we moved forward with this patch, would it
make it into Emacs 26.1?

Best,
Radon Rosborough

[1]: https://lists.gnu.org/archive/html/emacs-devel/2017-08/msg00154.html
[2]: https://lists.gnu.org/archive/html/emacs-devel/2017-08/msg00433.html
[3]: https://lists.gnu.org/archive/html/emacs-devel/2017-09/msg00023.html