[sponsor-patch] Support building with sbuild

Here's a proposed interface we could use:

Add a new option --builder or -B, which takes an argument of either "sbuild" or "pbuilder" (and obviously others if we add support for more builders in the future). If -B isn't specified, check SPONSOR_PATCH_BUILDER, and if that's unset, default to pbuilder (to maintain current behavior)

I'm also keen to create a u-d-t config file, that can remember the preferred build-system. I've (finally) filed LP: #681693 to track that.

Fix committed to lp:ubuntu-dev-tools. Please test it heavily if it works like you expected.

@Stefano: We don't need a config file, because we have the environment variable SPONSOR_PATCH_BUILDER.

This bug was fixed in the package ubuntu-dev-tools - 0.107

---------------
ubuntu-dev-tools (0.107) experimental; urgency=low

  [ Stefano Rivera ]
  * edit-patch: Detect quilt patch-system in 3.0 (quilt) packages without any
    patches yet.
  * wrap-and-sort:
    - Correct typo in options --wrap-allways -> --wrap-always
    - Sort debian/install as well as debian/*.install
    - Add one-space-indentation option: --short-indent
    - Remove null-entry from trailing comma in sorted lists
    - Add configurable debian directory location
    - Sort Architecture (LP: #681131)
    - Add --sort-binary-packages and --keep-first (LP: #681119)
  * grab-merge, syncpackage: Export DEB_VENDOR=Ubuntu when unpacking source
    packages. 3.0 (quilt) has optional per-vendor patch series.
  * pbuilder-dist:
    - Refactor to use subprocess.popen instead of os.system (LP: #398974)
    - Catch OSErrors when creating directories (LP: #671067)
    - Set HOME so pbuilder reads .pbuilderrc
    - Add bidirectional workarounds for LP: #599695 (pbuilder uses the host
      apt keyring). Complain if the target's keyring isn't installed.
  * Use dpkg-vendor in ubuntutools.misc.system_distribution(), cache result.

  [ Benjamin Drung ]
  * wrap-and-sort: Remove duplicate items from sorted lists.
  * syncpackage: Fix error message for failed downloads.
  * sponsor-patch: Support building with sbuild (LP: #681242).

  [ Daniel Holbach ]
  * submittodebian: rephrase boilerplate text to be more polite, add reminder
    to explain the patch sufficiently and add necessary information.

  [ Colin Watson ]
  * submittodebian: Encourage sending multiple independent pieces of the
    Ubuntu patch in separate bug reports.
 -- Benjamin Drung <email address hidden> Fri, 03 Dec 2010 00:14:25 +0100