Add a script to generate Python bundled provides

See https://src.fedoraproject.org/rpms/python-setuptools/pull-request/40

Strictly speaking, this is not an RPM generator, but:

 - it generates provides
 - it is tighly coupled with pythondistdeps.py

Usage:

 1. Run `$ /usr/lib/rpm/pythonbundles.py .../vendored.txt`

 2. Copy the output into the spec as a macro definition:

    %global bundled %{expand:
    Provides: bundled(python3dist(appdirs)) = 1.4.3
    Provides: bundled(python3dist(packaging)) = 16.8
    Provides: bundled(python3dist(pyparsing)) = 2.2.1
    Provides: bundled(python3dist(six)) = 1.15
    }

 3. Use the macro to expand the provides
 4. Verify the macro contents in %check:

    %check
    ...
    %{_rpmconfigdir}/pythonbundles.py src/_vendor/vendored.txt --compare-with '%{bundled}'

python-rpm-generators.spec

@@ -12,6 +12,7 @@ Source1:        python.attr
 Source2:        pythondist.attr
 Source3:        pythonname.attr
 Source4:        pythondistdeps.py
+Source5:        pythonbundles.py
 
 BuildArch:      noarch
 
@@ -35,7 +36,7 @@ cp -a %{sources} .
 
 %install
 install -Dpm0644 -t %{buildroot}%{_fileattrsdir} *.attr
-install -Dpm0755 -t %{buildroot}%{_rpmconfigdir} pythondistdeps.py
+install -Dpm0755 -t %{buildroot}%{_rpmconfigdir} *.py
 
 %files -n python3-rpm-generators
 %license COPYING
@@ -43,10 +44,12 @@ install -Dpm0755 -t %{buildroot}%{_rpmconfigdir} pythondistdeps.py
 %{_fileattrsdir}/pythondist.attr
 %{_fileattrsdir}/pythonname.attr
 %{_rpmconfigdir}/pythondistdeps.py
+%{_rpmconfigdir}/pythonbundles.py
 
 %changelog
-* Wed Jun 17 2020 Miro Hrončok <mhroncok@redhat.com> - 11-8
+* Fri Jun 26 2020 Miro Hrončok <mhroncok@redhat.com> - 11-8
 - Fix python(abi) requires generator, it picked files from almost good directories
+- Add a script to generate Python bundled provides
 
 * Thu May 21 2020 Miro Hrončok <mhroncok@redhat.com> - 11-7
 - Use PEP 503 names for requires