Added deprecation warnings to tests
refine Pow of Abs.
ipython: reenable mathjax and fix issue 3537.
Revert "Remove IPython sniffing" to fix part of issue 3728.

This reverts commit a4541e3af31eb33f4559d56e069d1150f332194b.
Don't load latex in ipython-console (terminal console).
ipython pretty printing tests should not rely on use_unicode=True.
If substitution in gosper_sum fails - take limit instead (issue 2934)
s/render_latex/use_latex/ and allow to pick png or mathjax.
_print_latex_png should also use the _can_print_latex logic.
ipython: check for the Terminal case instead of the kernel.
init_printing: Fix pretty_print=False for ipython.

Allow for pretty_print=False to completely disable pretty printing.
Use formatter.for_type instead of formatter.for_type_by_name which
seems to be buggy. Fixes issue 3604 and also cleans up the code.
Don't start ipython with init_session().

By default, don't start ipython with init_session() launched from
standard python. Launching ipython can still be requested explicitly
with init_session(ipython=True).

The logic to try to load ipython if available else falls back to
standard python is moved to bin/isympy.

Fixes issue 3292.
Plain text pretty printing of containers.

Don't change the plaintext printing of containers unless they
contain only SymPy types.

Fixes issue 3513.
Clean up unused functions.
Add a refine_Relational handler.

Allows refine(x < 0, Q.is_true(x<0)) == True
and refine(Piecewise((1, x<0), (3, True)), Q.is_true(x<0)) == 1.
Fix issue 3728
SymPyDeprecationWarnings raise an error in the tests
Merge branch 'master' into deprecation_warning_tests
Fix an import
remove hack2 from xreplace