Restore support for non-contiguous PyArrays, fix f_contiguous, simplify copy(::PyArray)

[JobJob]

Changes by commit

1. Add support for non-contiguous PyArrays: Restore support for non-contiguous PyArrays (I think they used to work before PyArray conversion speedups and PyArrayFromBuffer #487?)
2. Fix f_contiguous for 1d arrays: without this non-contiguous 1d PyArrays could have the f_contig flag set incorrectly to true. This would cause an incorrect conversion to julia for such arrays with a convert(PyAny, non_contig_1d_array) (see the [1,0,1,0] example in Use native sizes by default when parsing buffer format string #621/the "1d non-contiguous" testset in this PR)
3. Simplify Copy(::PyArray): With f_contiguous correct for 1d, copy(::PyArray) could be simplified

[JobJob]

Naughty naughty...

[stevengj]

Thanks!