Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

A number of places in the source tree still reference cuad.* after
sio(4) was deprecated by uart(4).

s/cuad/cuau/g/

PR: docs/171533
Reviewed by: imp
Approved by: cperciva (implicit)
MFC after: 3 weeks

Catch up with PHK's sio(4) cuaa->cuad rework [sys/dev/sio/sio.c rev. 1.456].

Major PicoBSD update by luigi with some debugging help from myself.

. Now builds on -STABLE (-CURRENT is broken due to bugs)
. etc directory contents centralized instead of in each
type directory (can exclude & override as desired)
. Removed extraneous language files (lang files for rc really necessary?)
. dialog-based build tool with support for custom floppy builds
. MFS image loads as a mfs_root module instead of compiled into kernel

THIS IS BROKEN ON CURRENT. I'll MFC to -STABLE immediately following.
luigi tells me I have an OK from jkh on the MFC.

Submitted by: luigi