Copy stable/11@r303970 to releng/11.0 as part of the 11.0-RELEASE
cycle.

Prune svn:mergeinfo from the new branch, and rename it to RC1.

Update __FreeBSD_version.

Use the quarterly branch for the default FreeBSD.conf pkg(8) repo and
the dvd1.iso packages population.

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

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

Make image_copyout_zeroes() an interface function.

Add image_data() for checking whether a sequence of blocks has data.
Use this for VHD and VMDK to avoid allocating space in the image
for empty sectors.

Note that this negatively affects performance because mkimg uses a
temporary file for the intermediate storage. When mkimg has better
internal book keeping, performance can be significantly improved.

Add VHD support to mkimg(1). VHD is used by Xen and Microsoft's Hyper-V
among others.

Add an undocumented option for unit testing (-y). When given, the image
will have UUIDs and timestamps synthesized in a way that gives identical
results across runs. As such, UUIDs stop being unique, globally or
otherwise.

VHD support requested by: gjb@

MFuser/marcel/mkimg:
Add support for different output formats:
1. The output file that was previously written is now called the raw format.
2. Add the vmdk output format to create VMDK images.

When the format is not given, the raw output format is assumed.

Add image_get_size() so formats can query about the image size.
Create the VMDK (embedded) descriptor file and round its size
to a multiple of 512.

TODO: We need the name of the output file -- it's in the extent
description. For now, just use "mkimg.vmdk".

Provide a file-based implementation for the image API. This almost
copies the logic verbatim from mkimg.c to image.c. The difference
is that in image.c the temporary file is always created, whereas
before we only created a temporary file when writing to stdout.

Cleanup mkimg.c now that the song and dance of using a temporary
file is gone.

Switch to the image API:
1. Replace calls to mkimg_set_size() with calls to image_set_size()
2. Remove the mkimg_set_size() function
3. As above but for mkimg_write() and image_write()

Note that this breaks mkimg(1). The image API has no implementation.
Hence doing it on my branch :-)

Add image.c and image.h. These files will contain functions to implement
the management of the raw image that's being created. The most notable of
the API is that there's no file descriptor argument. This is because the
image is managed in memory.

Once we have the in-memory (raw) image, we can write it out acording to
different formats. This two-pass approach shields schemes from formats
and formats from schemes.