Log Message:
xfce4-dev-tools: update to 4.13.0

Change log:

4.13.0
======
- Merge exo-csource modifications in xdt-csource
- xdt-csource will replace exo-csource (projects using exo-csource needs to be \ 
updated)
- The work started in issue #6449 but the full migration has never been done.
- Remove svn support in xdt-autogen
- Simplify a bit the XDT_AUTOGEN_REQUIRED_VERSION detection
- Remove the check of the unused doc submodule
- Remove useless macros: m4macros/xdt-python.m4 and m4macros/xdt-xfce.m4 are not used
- Remove xdt-commit, used to generate Changelog, now done via make distcheck
- No -Wshadow flag for enable_debug=full (bug #11637). Use it only for \ 
enable_debug=yes.