plotutils-2.6-2.11

- remove dependendy on gpg-offline, this is now part of the
  standard source services
- Use %license (boo#1082318)

- Call gzip -n to make build fully reproducible

- Restrict xorg library requires to the mininum needed.
- BUild C++ bits with -fvisibility-inlines-hidden.

- Do not remove lex/yacc code as current bison generate broken
  code (fix for bnc#829479, depends on bnc#829497)
- Add plotutils-hershey_glyphs.patch to avoid arithmetic overflow
  in Hershey pointing hands glyphs
- Add plotutils-man-spline.patch as there is no --number-of-intervals
  but --no-of-intervals option
- Add plotutils-postscript.patch to avoid broken postscript due not
  initialized variable

- Cleanup spec file
- Add Source URL, see https://en.opensuse.org/SourceUrls
- Add GPG checking

- update license to new format

- build also with libpng15
  * libpng15.patch

- prepare spec file for dropping SuSEconfig.fonts (openFATE#313536)

- add libtool as buildrequire to avoid implicit dependency

- Update to version 2.6 as this fix a copyright problem of mixing
  GPL and non-commercial code (bnc#465378)