Add the mkisofs package to the Windows mkbuildmachine scripts.

This adds the genisoimage command. Also update the cygwin installer
checksum as there is a new one.

OXT-65

Signed-off-by: Ross Philipson <ross.philipson@gmail.com>
Add support for generating a Windows only tools ISO

This will not break existing build machines that do not have
the genisoimage for cygwing. Once aded the stage step will start
creating the ISO.

OXT-65

Singed-off-by: Ross Philipson <ross.philipson@gmail.com>
Merge pull request #43 from rossphilipson/mkisofs

Add support for generating a Windows only tools ISO
OE: Move local build config to openxt.git and use build/ as TOPDIR.

This commit moves the local build metadata out of the xenclient-oe.git
repo and into openxxt.git. These things aren't typically part of a meta
layer. Turning xenclient-oe.git into a meta layer means moving these
to a new home in openxt.git. Minor edits to these files have been made
so that the build TOPDIR is build/ instead of build/oe/.

bb: Move the helper script 'bb' from xenclient-oe.git to the the openxt.git
    build directory.
bblayers.conf: Move the main 'conf' directory and the bblayers.conf file from
    xenclient-oe.git to openxt.git.
do_build.sh: Fixup paths to find the new location of the build output and
    configuration.
.gitignore: Be a bit more specific about ignored build
    files.

0XT-23

Signed-off-by: Philip Tricca <flihp@twobit.us>
[OXT-24] Treat the xenclient-oe.git repo like it was any other meta layer.

We clone it using the same mechanism we use for the other meta layers
and we clone it in the same location. Also I've started calling it
'meta-openxt' where possible. The remote still needs to be renamed
but it's not worthy of the name yet :)