Provide pre-built Ubuntu LEB images from snapshots

[asac, Dec 12, 2011]: Let's make this happen early next year. Moving to an actively PMed backlog so this gets on the official radar.
[rsalveti, Jan 31, 2012]: Andy can you please update the blueprint and work items to reflect the work that needs to be done to have daily pre-built images, like what you do for the released ones?
[dzin, Feb 3, 2012] Please add headline and acceptance criteria.
[rsalveti, Feb 21, 2012] Andy, can you please describe why you're currently blocked? This way the pm can follow it up properly.
[doanac, Feb 21, 2012] Ricardo - the two related bugs I added 746075 and 933494. 933494 is the more important of the two.
[rsalveti, Feb 23, 2012] Could not check bug 933494, guess it's private. For 746075 we just need to enable the pre-hook and run a simple script to accept the licenses we support, but probably something that'll take at least one more day. Too bad we're unable to finish this blueprint for this release, but it should be feasible for 12.03.
[doanac, April 2, 2012] The publish portion of the script still does not work. Waiting for answers from Deepti.
[dzin, April 2, 2012] Blocked, moving to 12.04
[deepti, April 3, 2012] It appears that the directory /srv3/snapshots.linaro.org/www/oneiric/ into which we are targeting to move our artifacts do not have appropriate permissions to write into the directory. Though linaro-ci-publish is part of the group which owns the directory, there is no write permission for the group on this directory and hence it fails silently without giving any error messages.
I spoke to tiaz from IS to request him to give the write permissions for group. Now the write permission for the group is granted and the publish to s.l.o should work.
Please test it and let me know.
[deepti, April 4, 2012] The permissions on the /srv3/snapshots.linaro.org/www/oneiric/ are reverted back to not have the g+w on it. As informed by bradm from IS this morning this could be happening because of rsync of the directories the permissions are getting reset. He suggests me to have an RT raised for this to get fixed as he thinks it needs more investigation from their side as to get a proper fix for it. Meanwhile, Andy I would like to know if we really need to store the pre built images in /srv3/snapshots.linaro.org/www/oneiric directory or should we store them somewhere like /srv3/snapshots.linaro.org/www/prebuilt-images ??
[fboudra, 2012-04-04] As discussed with Andy, users expect the pre-built images under ${distribution} instead of a separated directory. I'm opening a RT ticket to get it fixed by IS.

Meta:
Roadmap id: LINUX2012-Improve-CI-for-Ubuntu-LEB
Headline: Pre-Built Ubuntu LEB images are now provided in a daily basis at snapshots.linaro.org.
Acceptance: daily jobs at jenkins producing the pre-built images, images available at snapshots.linaro.org for the main targets we have.

Work items:
Get agreement on what what image sizes to use for every image type so that users don't need to resize the root filesystem: DONE
Figure out how to best sync files (hwpacks, rootfs's) to jenkins: DONE
Figure out which l-m-c to use (ie latest stable from BZR?): DONE
Write a function for crawling snapshots.linaro.org (hopefully using direct fs access if IS can give us that) and find the latest hwpack/rootfs: DONE
Write a function to list all the hwpack+rootfs combinations that we're interested in, given the list of hwpack/rootfs returned by the crawler: DONE
Write a function that runs l-m-c for every combination above and places the resulting image in a staging area of releases.linaro.org: DONE
Publish the images on snapshots.linaro.org: DONE
Update existing wiki instructions and add instructions to resize root fs after burning to SD card as well as how to gunzip/dd image file on windows: DONE
Setup ci.linaro.org to run this job daily at 1900UTC: DONE