so long as we still use the version-specific externals modules to *create* the build tags (e.g. V6_7_13_EXT), we do not need to use the same modules when actually checking out source to build (e.g. V6_7_BUILD).  instead, we just always check out from "externals", and allow the fact that only certain parts of the externals tree have been tagged to get what we need.  this way, a) old build tags will always work, even if we change the externals in a given module b) we no longer have to maintain all these version and branch-specific V*_BUILD modules for externals (the only reason for seperate ones now is if we change the *source* directories we want to build).  this should simplify a lot of things and allow for better reproducability of older tags without any manual effort.
so long as we still use the version-specific externals modules to
*create* the build tags (e.g. V6_7_13_EXT), we do not need to use the
same modules when actually checking out source to build
(e.g. V6_7_BUILD).  instead, we just always check out from
"externals", and allow the fact that only certain parts of the
externals tree have been tagged to get what we need.  this way, a) old
build tags will always work, even if we change the externals in a
given module b) we no longer have to maintain all these version and
branch-specific V*_BUILD modules for externals (the only reason for
seperate ones now is if we change the *source* directories we want to
build).  this should simplify a lot of things and allow for better
reproducability of older tags without any manual effort.

mambelli/osg-bosco-marco,mambelli/osg-bosco-marco,djw8605/htcondor,htcondor/htcondor,djw8605/htcondor,djw8605/condor,bbockelm/condor-network-accounting,htcondor/htcondor,mambelli/osg-bosco-marco,djw8605/htcondor,zhangzhehust/htcondor,htcondor/htcondor,zhangzhehust/htcondor,djw8605/condor,neurodebian/htcondor,neurodebian/htcondor,mambelli/osg-bosco-marco,htcondor/htcondor,djw8605/condor,bbockelm/condor-network-accounting,djw8605/condor,zhangzhehust/htcondor,neurodebian/htcondor,djw8605/condor,djw8605/htcondor,neurodebian/htcondor,htcondor/htcondor,djw8605/condor,bbockelm/condor-network-accounting,djw8605/htcondor,djw8605/htcondor,djw8605/condor,djw8605/htcondor,mambelli/osg-bosco-marco,bbockelm/condor-network-accounting,mambelli/osg-bosco-marco,neurodebian/htcondor,bbockelm/condor-network-accounting,zhangzhehust/htcondor,djw8605/htcondor,htcondor/htcondor,zhangzhehust/htcondor,bbockelm/condor-network-accounting,neurodebian/htcondor,mambelli/osg-bosco-marco,neurodebian/htcondor,zhangzhehust/htcondor,zhangzhehust/htcondor,bbockelm/condor-network-accounting,zhangzhehust/htcondor,zhangzhehust/htcondor,djw8605/condor,bbockelm/condor-network-accounting,mambelli/osg-bosco-marco,htcondor/htcondor,djw8605/htcondor,neurodebian/htcondor,neurodebian/htcondor,htcondor/htcondor