Merge branch 'master' into HEAD

Conflicts:
	sympy/printing/theanocode.py
Adding more functionality to RootSystem
Removed old commented out lines
Added @XFAIL test
Updating classes to use __new__ instead of init
Merge pull request #2379 from Manoj-Kumar-S/constant

Added XFAIL test for dsolve
Merge pull request #2394 from skirpichev/3633-inconsistent-assumptions

Fix issue 3633: inconsistent assumptions
Fixing some doctest errors
Simplify debug() code; print a space between the arguments
Add many debug() calls to init_printing
Print debugging information to stderr
Change preview to use BytesIO instead of StringIO

This fixes it to work in Python 3. Since BytesIO is available in Python 2.6,
the use of StringIO has been deprecated. See
https://code.google.com/p/sympy/issues/detail?id=3984.

This fixes, in particular, init_printing(use_latex='png') in Python 3.
Merge branch 'master' into liefinalintegration

Conflicts:
	sympy/solvers/tests/test_ode.py
Merge pull request #2375 from flacjacket/iteritems_fix

Fix print_cache
Merge pull request #2359 from Manoj-Kumar-S/liefinalintegration

Integration of the Lie Group Solving method
Changed sym matrix doctest from is to ==
Merge branch 'master' into seriessolve

Conflicts:
	sympy/solvers/deutils.py
	sympy/solvers/ode.py
	sympy/solvers/tests/test_ode.py
MatrixElement._diff_wrt = True
Remove the verbose parameter.
Merge pull request #2370 from moorepants/theano-travis

First shot at Theano on Travis.