Log Message:
Updated package to latest version, 5.0.1. Changes (from 4.3) include:

dose3 (5.0) UNRELEASED; urgency=low
* finally implement keep_package/version/feature properly. The globalid
  index that was used to optionally encode the global constraints is
  now disappeared. This simplify the interface of the solver.
* massive refactoring. Change of API . All functions in Depsolver*
  accept a new paramenter "global_constraints" that is a vpkgformula
  enconding all packages that must be co-installed by by default with
  each request. This is used to properly encode debian essential packages
  without abusing 'Keep_package as before.
* Depsolver_int.{solve,init_solver_unit,init_solver_cache} have a new optional
  argument 'explain'. When false, reduce the memory footprint.
* Depsolver.{check_request,check_request_using} accept a new parameter dummy
  that can be used to pass arbitrary contraints as a cudf.package that is going
  to be coinstalled as part of the request and filtered out in the result.
* improvements to the documentation and test units
* add --compare to ceve when used with pef://
* improvements to distcheck --lowmem
* StdOptions.lastest now returns an integer to consider only the last n versions
  of each package
* API change : CudfAdd.latest
* API change : CudfAdd.inttovar -> CudfAdd.inttopkg
* API change : add parameter to check_request and check_request_using
* apt-cudf : package up or downgrades are expressed in a single
  "Install" request and that these do not show up as a \ 
"Remove" request anymore.
* StdOptions.DistribOptions.add_options are now different for each input ( ex.
  StdOptions.DistribOptions.add_debian_options )uu
* Debian.Printer.pp_* functions are now methods of the Debian.package class