Fix DotProduct example error

missing "{" "}".
x=torch.Tensor(1,2,3)  => x=torch.Tensor({1,2,3})
y=torch.Tensor(4,5,6)  => y=torch.Tensor({4,5,6})
Fixed PairwiseDistance example
added msg to recursive tester
SpatialConvolutionMM now support on-the-fly zero-padding.

Interface similar to cunn.SpatialConvolutionMM.

To get a layer where osize == isize, do this:
  local ksize = 5
  local padding = (ksize-1)/2
  local n = nn.SpatialConvolutionMM(ni,no, ksize,ksize, 1,1, padding)

Note: dW/dH still not supported on the CPU version (strides).
DepthConcat
Corrected getParamaters for partial views

Module:getParameters was incorrectly overwriting parameters that
were partial views on larger storages.
Fixed broken CosineDistance examples.
modernized MarginCriterion
adding addtional weights parameter to ClassNLLCriterion, which is 1D tensor assigning different weight to each class
Faster unit tests
Relax equality tests from exact precision 0.
Expecting exact precision 0 can lead to failing tests if underlying implementation changes, a high expected precision of say 1e-15 seem more appropriate (nntest.Power sometimes fails because of this)
adding scale to accGradParameters documentation
Typo