Merge branch 'es/init-no-separate-git-dir-in-bare'

Merge branch 'es/init-no-separate-git-dir-in-bare'

The purpose of "git init --separate-git-dir" is to initialize a
new project with the repository separate from the working tree,
or, in the case of an existing project, to move the repository
(the .git/ directory) out of the working tree. It does not make
sense to use --separate-git-dir with a bare repository for which
there is no working tree, so disallow its use with bare
repositories.

* es/init-no-separate-git-dir-in-bare:
  init: disallow --separate-git-dir with bare repository