Change the degree of some polynomials to be an Integer.

Polynomials over some fields, like RDF, used to be of type int and not Integer.
To be consistent, these were changed to return an Integer as well.
Fix some corner cases for partitions and partition tuples.
Merge branch 'develop' into public/combinat/fix_latex_partitions-16036

* develop: (155 commits)
  Updated Sage version to 6.2.beta6
  32-bit fix
  typo fixing
  fix int/long doctest
  trac #16032: These matrices should be sparse
  trac 16032: This can be simplified... :-P
  Correct typo in sage/symbolic/ring.pyx.
  Put comment in the code and add more examples.
  trac #16032: reviewer's remarks
  FiniteStateMachine.__add__ is the same as __or__
  trac #16032: Bug in IncidenceStructure.dual_design
  final edits
  more changes -- please check if I got your algorithm right, Travis
  Review changes from Ben.
  further optimizations
  Fixed KR doctest and documentation of q_dimension.
  Fixes for q-dims for general highest weight crystals.
  more optimizations
  Partial work for general HW crystals.
  Review changes and (minor) optimizations.
  ...
Added special case to ferrers diagram for the empty partition.
Trac 14984: Cannot plot functions that use mpmath if complex numbers occur in the image
Trac #16036: Fix corner cases of latex for partitions

{{{
sage: Partitions.global_options('exp_high')
sage: latex(Partition([])) # Boom
sage: Partitions.global_options('exp_low')
sage: latex(Partition([])) # Returns the empty string

}}}
There are likely others.

URL: http://trac.sagemath.org/16036
Reported by: tscrim
Ticket author(s): Travis Scrimshaw
Reviewer(s): Mike Zabrocki
Trac #12552: degree of polynomial_element is of type int

The degree of a polynomial over {{{RDF}}} is of type {{{int}}} and not a
sage Integer.

{{{
sage: R.<x> = RDF[]
sage: type(x.degree())
<type 'int'>
sage: x.degree().divides(6)
Error
}}}

This is not consistent with polynomials over other rings:

{{{
sage: R.<x> = QQ[]
sage: type(x.degree())
<type 'sage.rings.integer.Integer'>
sage: x.degree().divides(6)
True
}}}

The attached patch fixes this.

URL: http://trac.sagemath.org/12552
Reported by: saraedum
Ticket author(s): Julian Rueth
Reviewer(s): Ralf Stephan
Trac #14984: Cannot plot functions that use mpmath if complex numbers occur in the image

Currently, trying to plot a function which uses mpmath and returns a
complex number in the plotting domain will return an error. For example,

{{{
sage: from sage.libs.mpmath import utils
sage: import mpmath
sage: class Test(BuiltinFunction):
....:     def __init__(self):
....:         BuiltinFunction.__init__(self, name='test', nargs=1)
....:     def _evalf_(self, x, parent):
....:         return utils.call(mpmath.log, x, parent=parent)
....:
sage: test = Test()
sage: plot(test, x, -1, 1)
AttributeError: type object 'float' has no attribute 'complex_field'
}}}

URL: http://trac.sagemath.org/14984
Reported by: eviatarbach
Ticket author(s): Eviatar Bach
Reviewer(s): Ralf Stephan