Supporting OpenJDK in stable releases

Two primary issues:
- supporting releases older than precise
  - Separate armel package (6b18). Starting with 6b24, armel should build on arm.

  Strategy is to backport precise version into earlier releases
  - Package should work fine, may need some patches and testing
  Need to run TCK on older releases. This was run on Lucid.

  Strategy is to build for earlier releases and to test, and _then_ decide what to do based on results

  Can't migrate openjdk-6 to openjdk-7. About 700 packages depend on openjdk, and it's API incompatible. Only solution is to backport security fixes to openjdk-6, and try and enlist help from other users.

  Between Oneiric and Precise, the default switched from JAM to zero on arm. We should attempt to make the switch on older releases also for consistancy, but can fallback to JAM if it causes problems.

Other distros:
Contacted RHEL; they are planning a public announcement and won't discuss details of their maintenance plan until then.

SUSE does not include openjdk in their SLE (enterprise) releases, so they only need to maintain openjdk 6 in OpenSUSE for another year.

Work items:
[sbeattie] contact RHEL people to try and arrange co-maintenance (essential) (0.5): DONE
[james-page] find out icedtea's official position on openjdk-6 eol (high) (0.5): POSTPONED
[sbeattie] build precise package on older releases (essential) (3): DONE
[jibel] run test suite on stable releases (essential) (3): DONE
[james-page] contact eucalyptus team to test backports (medium) (0.5): DONE