[Torch] Support Python list, more realistic recurrent networks (#5306)
* use funcs from prelude, pass around convert_map
* get relay input type from user ishape
* handle tuple unpack
* experimenting with static tensor array
* use prelude concat instead of cons + rev
* minor clean up
* fix layer norm conversion bug, unwrap tensor array
* add infer shape on tensor array
* pass around prelude for now
* compile worked but runtime error
* fix tensor array wrapping
* begin list dynamic test
* is_list_dynamic first version
* finish dynamic list test
* a few fix
* use shape_of function if Any is found
* improve size conversion
* working on adding free vars to loop block
* fixed inlined inner loop issue
* clean up free var handling
* add support for tensor array concat
* adding ta concat on last axis
* fix concat, but got runtime error
* disable concat on axis -1 for now
* add lstm tests
* revert unrelated change
* fix stacked bidir test
* minor fix to test
* relax tol a bit, revert dnnl change to avoid conflict
* simplify infer type, use input tensor shape rather than concat shape
* more shape fix