Recent flake8 failures

In my fork of the repository, I am getting the following flake8 failures. It seems like a new version of flake8 was released recently, so this may have something to do with that. These seem like they should be fixed.

pytential/solve.py:211:21: W504 line break after binary operator
pytential/solve.py:212:21: W504 line break after binary operator
pytential/linalg/proxy.py:97:28: W504 line break after binary operator
pytential/linalg/proxy.py:164:28: W504 line break after binary operator
pytential/linalg/proxy.py:228:17: W504 line break after binary operator
pytential/linalg/proxy.py:578:21: W504 line break after binary operator
pytential/qbx/direct.py:48:13: W504 line break after binary operator
pytential/qbx/direct.py:65:13: W504 line break after binary operator
pytential/qbx/direct.py:68:13: W504 line break after binary operator
pytential/qbx/fmmlib.py:331:25: W504 line break after binary operator
pytential/qbx/fmmlib.py:338:17: W504 line break after binary operator
pytential/symbolic/stokes.py:479:41: W504 line break after binary operator
pytential/symbolic/primitives.py:290:13: W504 line break after binary operator
pytential/symbolic/primitives.py:904:13: W504 line break after binary operator
pytential/symbolic/primitives.py:1108:21: W504 line break after binary operator
pytential/symbolic/pde/cahn_hilliard.py:57:21: W504 line break after binary operator
pytential/symbolic/pde/cahn_hilliard.py:61:25: W504 line break after binary operator
pytential/symbolic/pde/maxwell/__init__.py:55:-335: W605 invalid escape sequence '\e'
pytential/symbolic/pde/maxwell/__init__.py:55:-327: W605 invalid escape sequence '\o'
pytential/symbolic/pde/maxwell/__init__.py:93:-335: W605 invalid escape sequence '\e'
pytential/symbolic/pde/maxwell/__init__.py:93:-327: W605 invalid escape sequence '\o'
pytential/symbolic/pde/maxwell/__init__.py:233:13: W504 line break after binary operator
pytential/symbolic/pde/maxwell/__init__.py:235:13: W504 line break after binary operator
pytential/symbolic/pde/maxwell/__init__.py:237:13: W504 line break after binary operator
pytential/symbolic/pde/maxwell/__init__.py:239:13: W504 line break after binary operator
pytential/symbolic/pde/maxwell/waveguide.py:564:21: W504 line break after binary operator
pytential/symbolic/pde/maxwell/waveguide.py:591:17: W504 line break after binary operator
test/test_global_qbx.py:147:21: W504 line break after binary operator
test/test_global_qbx.py:172:21: W504 line break after binary operator
test/extra_curve_data.py:87:13: W504 line break after binary operator
test/extra_curve_data.py:137:17: W504 line break after binary operator
test/extra_curve_data.py:141:17: W504 line break after binary operator
test/extra_curve_data.py:152:5: W504 line break after binary operator
test/extra_curve_data.py:153:5: W504 line break after binary operator
test/extra_curve_data.py:154:5: W504 line break after binary operator
test/extra_curve_data.py:155:5: W504 line break after binary operator
test/extra_curve_data.py:156:5: W504 line break after binary operator
test/extra_curve_data.py:157:5: W504 line break after binary operator
test/extra_curve_data.py:158:5: W504 line break after binary operator
test/extra_curve_data.py:164:5: W504 line break after binary operator
test/extra_curve_data.py:165:5: W504 line break after binary operator
test/extra_curve_data.py:166:5: W504 line break after binary operator
test/test_layer_pot.py:420:17: W504 line break after binary operator
test/test_layer_pot_eigenvalues.py:169:17: W504 line break after binary operator
test/test_layer_pot_eigenvalues.py:201:17: W504 line break after binary operator
test/test_layer_pot_eigenvalues.py:221:21: W504 line break after binary operator
test/test_layer_pot_eigenvalues.py:280:17: W504 line break after binary operator
test/test_scalar_int_eq.py:716:17: W504 line break after binary operator