gnu: Add diffstat.

* gnu/packages/version-control.scm (diffstat): New variable.

gnu: Add missing copyright line

* gnu/packages/maths.scm: Add copyright line missing from 3de01d3.

gnu: petsc: Add input superlu.

* gnu/packages/maths.scm (petsc): Configure with superlu support.

gnu: Add superlu

* gnu/packages/maths.scm (superlu): New variable

gnu: qemu: Upgrade to 2.0.0.

* gnu/packages/qemu.scm (qemu-headless): Upgrade to 2.0.0.

gnu: Add petsc

* gnu/packages/maths.scm (petsc): New variable.
  (petsc-complex): New variable.
* gnu/packages/patches/petsc-fix-threadcomm.patch: New patch.
* gnu-system.am (dist_patch_DATA): Add it.

gnu: Add abbaye.

* gnu/packages/games.scm (abbaye): New variable.

gnu: Propagate necessary inputs for sdl-image.

* gnu/packages/sdl.scm (sdl-image): Propagate jpeg, png, and tiff
  libraries.

gnu: Add sudo.

* gnu/packages/admin.scm (sudo): New variable.

gnu: calcurse: Fix module definition.

* gnu/packages/calcurse.scm: Define calcurse module correctly.

gnu: gmsh: Fix typos

* gnu/packages/maths.scm (gmsh): Fix typo and space aftern
  end-of-sentence.

gnu: Add gmsh

* gnu/packages/maths.scm (gmsh): New variable

gnu: guile-ncurses: Build with Unicode support.

* gnu/packages/guile.scm (guile-ncurses)[arguments]: Pass
  "--with-ncursesw".

gnu: screen: Upgrade to 4.2.1.

* gnu/packages/screen.scm (screen): Upgrade to 4.2.1.

gnu: mcron: Upgrade to 1.0.7.

* gnu/packages/guile.scm (mcron): Upgrade to 1.0.7.
  Use GUILE-2.0 instead of GUILE-1.8; add 'native-inputs' field.

gnu: soprano: Add input clucene.

* gnu/packages/rdf.scm (soprano): Add input clucene and patch the cmake
    file looking for it.
* gnu/packages/patches/soprano-find-clucene.patch: New file.
* gnu-system.am (dist_patch_DATA): Register the patch.

gnu: soprano: Upgrade to 2.9.4.

* gnu/packages/rdf.scm (soprano): Upgrade to 2.9.4.

guix: cmake: Add input and package libraries to the rpath, and adapt package
  definitions accordingly.

* guix/build/cmake-build-system.scm (configure): Add flags.
* gnu/packages/maths.scm (lapack): Drop special code.
* gnu/packages/ssh.scm (libssh): Drop special code.
* gnu/packages/slim.scm (slim): Drop special code and enable shared library.

Co-authored-by: Eric Bavier <bavier@member.fsf.org>

gnu: soprano: Add native input doxygen.

* gnu/packages/rdf.scm (soprano): Add native input doxygen.

gnu: doxygen: Add propagated input graphviz.

* gnu/packages/doxygen.scm (doxygen): Add propagated input graphviz.