Added test cases for issue 4091
Move dispersion code to polynomials module
Proper documentation for all dispersion stuff
Added test that checks for LaTeX representations.
Fixed tests for Python 3 unicode.
Merge pull request #2717 from avichaldayal/4091_log

Solvers: changed force=True from false when combining log
Refactored sympy.core.relational.

Broke out logic from the Relational class into subclasses.  Simplified the
logic without modifying it.  Eliminated the helper functions, replacing with
aliases to the relevant classes.  Added docstrings for Relational, Equality,
and Unequality.
Fix github's issue #2725
Add mpmath's translation for Abs
Tests pass on Python 2/3, IPython 0.13.2/0.1.1.
Merge pull request #2683 from moorepants/ipython-printing

Improvements to IPython printing: strings, floats, and ints.
Added Vectors and Dyadics to IPython printing.

The Vector and Dyadic objects in the mechanics module have the capability to
print as LaTeX. I've added these to the init_printing `_can_print_latex` check
and now they render in the notebook properly. This fixes issue #2584.
Changed to \cdot for separating unit vectors and scalars.
Removed \cdot and went with no space.
Merge pull request #2687 from moorepants/mechanics-ipython

Mechanics Vectors and Dyadics print in LaTeX with init_printing()
Fixes Vector latex printing in issue #2727.
doctest fix
Merge pull request #2728 from moorepants/vector-printing

Fixes Vector latex printing in issue #2727.
Merge pull request #2726 from skirpichev/gh2725

Fix github's issue #2725
space removed