Trac 17366: the degre method for elements of multivariate polynomials rings
should convert its argument to an element of the parent ring.
Trac 17366: additional minor changes
Stop patching sphinx-build
Trac #17316: RegularMatroid.is_isomorphic returns false positives

Example:

{{{
from sage.matroids.advanced import *
Mnew = RegularMatroid(groundset=range(12), matrix=Matrix(ZZ,
[[ 1, 0, 0, 0, 1, 0, 0,-1,-1, 0, 1, 0],
 [ 0, 1, 0, 0,-1, 1, 0, 0, 0, 0, 0, 0],
 [ 0, 0, 1, 0, 0,-1, 1, 0, 1, 0,-1, 0],
 [ 0, 0, 0, 1, 0, 0,-1, 1, 0, 0, 0, 0],
 [ 0, 0, 0, 0, 0, 1,-1, 0, 0, 1, 1, 0],
 [ 0, 0, 0, 0, 1, 0, 0,-1,-1, 0, 0, 1]]))

Nnew = RegularMatroid(groundset=range(12), matrix=Matrix(ZZ,
[[1,0,0,0,0,0,1,1,0,0,1,0],
 [0,1,0,0,0,0,1,0,1,0,1,0],
 [0,0,1,0,0,0,1,0,0,1,1,0],
 [0,0,0,1,0,0,1,1,0,0,0,1],
 [0,0,0,0,1,0,1,0,1,0,0,1],
 [0,0,0,0,0,1,1,0,0,1,0,1]]))

print Mnew.is_isomorphic(Nnew)
print len(Mnew.circuits()) == len(Nnew.circuits())
}}}

{{{
True
False
}}}

URL: http://trac.sagemath.org/17316
Reported by: Stefan
Ticket author(s): Rudi Pendavingh
Reviewer(s): Stefan van Zwam
Trac #12703: Update GLPK to 4.55

Old versions (at least till 4.47) fail to build when link-time
optimization (LTO, `gcc -flto ...`) is enabled.

While `configure` shows an error message, it continues normally and
doesn't exit with an error.  Only later during the build, a shell syntax
error caused by `libtool` makes the build finally fail.

New versions have been re-autotoolized with more recent autotools.

New versions also unconditionally use their own zlib, this is
circumvented by patching in the spirit of what Red Hat does.

Finally we let GLPK build shared lib on Cygwin.

Upstream tarball:
* http://ftp.gnu.org/gnu/glpk/glpk-4.55.tar.gz

URL: http://trac.sagemath.org/12703
Reported by: leif
Ticket author(s): Leif Leonhardy, Jean-Pierre Flori
Reviewer(s): Nathann Cohen, Volker Braun
Trac #17366: for multivariate polynomial rings, degree method should convert its argument

As reported at #17205:
{{{
    sage: x, y = ZZ['x','y'].gens()
    sage: GF(1091)['x','y'].random_element().degree(x) ### works
    sage: GF(3037000453)['x','y'].random_element().degree(x) ### fails
}}}
The 2nd and 3rd lines are handled by different code, one from
`multi_polynomial_libsingular.pyx` and one from
`multi_polynomial_element.py`. The first tries to convert the argument
`x` into the parent ring, but the second does not.

The point here is to reconcile the approaches: always try to convert the
argument into the parent ring.

URL: http://trac.sagemath.org/17366
Reported by: jhpalmieri
Ticket author(s): John Palmieri
Reviewer(s): Volker Braun
Trac #17369: sphinx-build is broken

The script `$SAGE_LOCAL/bin/sphinx-build` (which is copied over from
`build/pkgs/sphinx/patches/sphinx-build`) is broken since it refers to
the wrong version.

The Sage documentation build no longer uses the `sphinx-build` script,
so this wasn't noticed immediately. Manually calling this script gives
{{{
Traceback (most recent call last):
  File "/usr/local/src/sage-git/local/bin/sphinx-build", line 5, in
<module>
    from pkg_resources import load_entry_point
  File "build/bdist.linux-x86_64/egg/pkg_resources.py", line 2817, in
<module>
  File "build/bdist.linux-x86_64/egg/pkg_resources.py", line 451, in
_build_master
  File "build/bdist.linux-x86_64/egg/pkg_resources.py", line 464, in
_build_from_requirements
  File "build/bdist.linux-x86_64/egg/pkg_resources.py", line 639, in
resolve
pkg_resources.DistributionNotFound: Sphinx==1.1.2
make: *** [html] Error 1
}}}

URL: http://trac.sagemath.org/17369
Reported by: jdemeyer
Ticket author(s): Jeroen Demeyer
Reviewer(s): Karl-Dieter Crisman