Update to sagemath 8.2.

Also:
- Create the sagemath-data-combinatorial_designs subpackage.
- Create the sagemath-notebook-export subpackage.
- Unbundle the LaTeX makecmds style.
- Install LaTeX style files in a more canonical place.

sagemath-lrslib.patch

@@ -1,21 +1,12 @@
 diff -up src/sage/geometry/polyhedron/base.py.orig src/sage/geometry/polyhedron/base.py
---- src/sage/geometry/polyhedron/base.py.orig	2017-11-08 08:21:45.693203621 -0500
-+++ src/sage/geometry/polyhedron/base.py	2017-11-08 08:21:56.893204050 -0500
-@@ -22,7 +22,6 @@ from sage.structure.element import Eleme
- from sage.structure.richcmp import rich_to_bool, op_NE
- 
- from sage.misc.all import cached_method, prod
--from sage.misc.package import is_package_installed
- 
- from sage.rings.all import QQ, ZZ, AA
- from sage.rings.real_double import RDF
-@@ -4188,10 +4187,6 @@ class Polyhedron_base(Element):
+--- src/sage/geometry/polyhedron/base.py.orig	2018-05-16 13:31:55.930138769 -0600
++++ src/sage/geometry/polyhedron/base.py	2018-05-16 13:35:12.219428900 -0600
+@@ -4281,9 +4281,6 @@ class Polyhedron_base(Element):
  
               David Avis's lrs program.
          """
 -        if not is_package_installed('lrslib'):
--            raise NotImplementedError('You must install the optional lrslib package '
--                                       'for this function to work')
+-            raise PackageNotFoundError('lrslib')
 -
          from sage.misc.temporary_file import tmp_filename
          from subprocess import Popen, PIPE