REL: change Sphinx version in release script to 1.1.3.

Version 1.0.4 was used till now, but has become too old.  New version gives far
fewer warnings and thereby increases the reference guide with O(100) pages that
previously got lost.

Also update current Cython version number.

doc/HOWTO_RELEASE.rst.txt

@@ -74,7 +74,7 @@ each platform. At the moment this means:
 Cython is not needed for building the binaries, because generated C files from
 Cython sources are checked in at the moment. It is worth keeping an eye on what
 Cython versions have been used to generate all current C files, it should be
-the same and most recent version (0.12.1 as of now).
+the same and most recent version (0.16 as of now).
 
 Fortran: on OS X gfortran from `this site <http://r.research.att.com/tools/>`_ 
 is used. On Windows g77 (included in MinGW) is the current default, in the future 

pavement.py

@@ -115,7 +115,7 @@
 SUPERPACK_BINDIR = os.path.join(SUPERPACK_BUILD, 'binaries')
 
 options(bootstrap=Bunch(bootstrap_dir="bootstrap"),
-        virtualenv=Bunch(packages_to_install=["sphinx==1.0.4", "numpydoc"],
+        virtualenv=Bunch(packages_to_install=["sphinx==1.1.3", "numpydoc"],
                          no_site_packages=False),
         sphinx=Bunch(builddir="build", sourcedir="source", docroot='doc'),
         superpack=Bunch(builddir="build-superpack"),