[MERGE] bzr.exe: move builtin plugins out of library.zip to directory 'plugins'

[Ian Clatworthy]

Robert Collins wrote:

> The automatic plugin management stuff should not touch built in plugins.
> They are not truely independent - e.g. bundles /depend/ on those plugins
> being present and of the correct version.

I assume your referring to the multiparent plugin?

If we have core stuff depending on plugins, bundled or otherwise, I
think that's most undesirable from a layering perspective. If it's just
the multparent plugin, any reason why we shouldn't move it into the core?

Ian C.