Add conv layer and layer tests

Reviewed By: xianjiec

Differential Revision: D5569206

fbshipit-source-id: ed836315f3ee4d7983da94f2633a3085fe99194d

comment out unused parameters

Summary: This uses `clang-tidy` to comment out unused parameters (in functions, methods and lambdas) in fbcode. Cases that the tool failed to handle are fixed manually.

Reviewed By: igorsugak

Differential Revision: D5454343

fbshipit-source-id: 5dee339b4334e25e963891b519a5aa81fbf627b2

fix CuDNN RecurrentOp Gradient init

Summary: CuDNN RecurrentNet GradientOp did not pass the DROPOUT information to the initializer, causing incorrect scratch space size to be estimated. We have an assertion encorcing that scratch space is same for forward and backward ops, so this failed an assertion. We currently hard-code dropout to be 1.0, so this has had no effect on correctness in our tests. For some reason with num_layers=1 there wasn't an issue, but with num_layers>=2, the scratch space size was different.

Reviewed By: salexspb

Differential Revision: D4904715

fbshipit-source-id: 780266c5ecf1f7a32387edcb6fc498a13ac782ac

ubuntu installation instuctions for v0.6.0 (facebookarchive#244)