updated workflow submodule to 31fe655
upgrade to Git::Repsitory test plugin v.002

* replace File::Temp with calls to new_tmp_repo()
* replace install_hook() subroutine with call to install_hook() method
Check the existence of the tabix file separately.

Otherwise a previously existing result would see the VCF symlink updated
but a crash on the tabix symlink.
Add a true value to the end of the module.
Consolidate VCF/tabix symlinking into Base
Deduplicate code--call into the Base version.

Hopefully one day this might be in a common base class of all three
modules that use it, but this seemed better than leaving divergent
duplicated code around.
Wingspan now has a default of 0, as it is required but was not marked as such
Merge branch 'master' into gb_master