In a large team setting is often more desirable to use an external source project.  The externalsrc.bbclass today disables all the setscene tasks and integration with the fetcher.

For a large team the CM integration with the fetcher is much more desirable for a couple of reasons.

  1) sstate resuse
  2) branch and track changes in the external git area


It would be ideal to allow a recipe to operate with either AUTOREV or a specific rev but instead of looking at the upstream to look for any of the revision information in the local archive.


The requirements for the gitexternalsrc:
  1) The fetcher looks locally instead of remotely
     ** It might be nice to optionally fetch the remote upstream in the 
        case that 
  2) If using a specific rev, it will get checked out at fetch time
     just like an upstream recipe would work
  3) Allow for a separated build area if needed or allow for an in-tree build
  4) Conditionally, allow for a cleanup rule which will actually clean up 
     using operations like "git clean -f -d"
  5) sstate works properly
  6) Allow the ls-remote to be local for computation of recipes that
     use a SRCREV in the version and or name