Added slow tests to the travis system.
Timeout the slow tests in Travis to less than 10 minutes
Seconds, not minutes
Run the slow tests in Travis with a timeout of 5 minutes
Fix the failing finite_rv slow tests
Merge branch 'master' into travis-slow-tests
Add doctest to with_metaclass()
Fix @slow failure in test_query.
Remove deprecated Real class and is_Real property of Basic, see issue 1721
Remove deprecated 'each_char' option for symbols(), see issue 1919
Add XFAIL for test_heurisch failure.
Merge branch 'master' into tests

Conflicts:
	.travis.yml
	bin/test_travis.sh
Merge pull request #2391 from asmeurer/with_metaclass_doc

Add doctest to with_metaclass()
Merge pull request #49 from jrioux/tests

Fix @slow failure in test_query.
Fix atan2._eval_evalf().
Less stringent @slow tests in test_trigonometric.
Testing all the multiples of pi/255 is just way too slow.
Merge pull request #50 from jrioux/tests

Fix slow tests in test_trigonometric.
Reduce Travis slow test timeout by a minute

See if this makes the slow tests finish in under 50 minutes.
Merge pull request #2313 from skirpichev/deprecated-0.7.0

Remove some stuff, deprecated since 0.7.0