python: doc: Remove generated files, put rules in Makefile.
* lang/python/doc/Makefile.am (EXTRA_DIST): Remove files not distributed like files under meta. * Add rules to generate .rst and .texi files. * lang/python/doc/rst: Remove .rst files to be generated. * lang/python/doc/texinfo: Remove .texi files to be generated.
- GnuPG-bug-id: T4275
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>