Mostly tests: clean-up deprecation warnings and apply PEP8 style

 - Find PendingDeprecationWarning (using `python -W all setup.py test`),
   and review with the following substitutions:
   - failIf -> assertFalse
   - failUnless -> assertTrue
   - failUnlessEqual -> assertEqual
   - failUnlessAlmostEqual -> assertAlmostEqual
 - Complete a few `unittest.TestLoader()` -> `loader` aliases in tests
 - use pep8 utility on tests to identify and correct for PEP8: "Style Guide
   for Python Code"
 - Add GEOS version and speedups status at top of tests, since this is
   useful info to see
 - setup.py test now returns a bad (non-zero) exit code for failed tests,
   which is crucial for TravisCI

Other fixes (than from tests):
 - Fix a few `geom.to_wkt()` to using the `geom.wkt` property (and
   the equivalent for wkb)
 - Deprecate shapely.iterops.geos_from_geometry(geom) (appears redundant
   and is without documentation)
 - Correct several ResourceWarning from setup.py, using "with" statements
 - Remove setup.cfg, since it doesn't do anything (right now)