Returned sandbox/softsign.py for backward compatibility. Fixed tests.

Theano.pyproj

@@ -137,6 +137,7 @@
     <Compile Include="theano\sandbox\neighbourhoods.py" />
     <Compile Include="theano\sandbox\neighbours.py" />
     <Compile Include="theano\sandbox\rng_mrg.py" />
+    <Compile Include="theano\sandbox\softsign.py" />
     <Compile Include="theano\sandbox\solve.py" />
     <Compile Include="theano\sandbox\symbolic_module.py" />
     <Compile Include="theano\sandbox\test_multinomial.py" />

theano/sandbox/softsign.py

+from __future__ import absolute_import, print_function, division
+from theano.tensor.nnet.nnet import softsign
+
+softsign = softsign  # otherwise build fails due to unused import

theano/tensor/nnet/tests/test_nnet.py

@@ -35,8 +35,10 @@ from theano.tensor.nnet import (categorical_crossentropy,
 from theano.tensor import matrix, vector, lvector, scalar
 from theano.tensor.nnet.nnet import softsign
 from theano.tensor.tests.test_basic import (makeBroadcastTester, check_floatX,
+                                            _good_broadcast_unary_normal_float_no_complex,
                                             upcast_int8_nfunc)
 
+
 class T_sigmoid(unittest.TestCase):
 
     def setUp(self):
@@ -1706,5 +1708,6 @@ SoftsignTester = makeBroadcastTester(
     op=softsign,
     expected=upcast_int8_nfunc(lambda inputs: check_floatX(
         inputs, inputs/(1.0+numpy.fabs(inputs)))),
+    good=_good_broadcast_unary_normal_float_no_complex,
     name='SoftsignTester',
 )