made nn a rock
corrected rockspec (to work under windows)
Merge remote-tracking branch 'upstream/master'
nn: better flags
nn: link dir for windows
Merge remote-tracking branch 'upstream/master'
nn: install doc at the right place
nn: fix dok [anchors must be before header names]
Merge remote-tracking branch 'upstream/master'

Conflicts:
	extra/cuda/CMakeLists.txt
	extra/nn/CMakeLists.txt
	pkg/CMakeLists.txt
	rocks/nn/doc/README.md
Merge remote-tracking branch 'upstream/master'

Conflicts:
	pkg/CMakeLists.txt
	pkg/torch/CMakeLists.txt
	rocks/gnuplot/doc/README.md
Fixed PairwiseDistance for odd Lp norms
Fixed the bprop in PairwiseDistance for pnorms other than one.  The gradInput has always been wrong it seems; the sign of the gradient is correct but the magnitude was wrong.  I also added a test in extra/nn/test/test.lua for nn.PairwiseDifference, which tests both the batch and non-batch code paths for a few different p-norms.
it seems like torch.abs() doesn't have a cuda implementation, so the previous commit would fail when PairwiseDistance():cuda() was called.
fixed a bug in Pairwise distance when the output Lp norm is zero (which results in a divide by zero issue).  Rewrote PairwiseDistance following Clement's suggestion to only have one codepath.  Fixed a small bug in extra/test/test.lua where the input to the non-batch fprop test was zero.
updated rockspec to point on torch/nn
going back on Clement's suggestion.  It was a good idea, but we're needlessly loosing performance in the 1D case with the input clone.
Extend assertError and fix global

Two new asserts: assertErrorMsg and assertErroObj,
to compare the actual error message or object returned.
Add assertErrorPattern
Make error message clearer
Add Tester:assertalmosteq()