add print_active_device flag

Fix tests for image2neibs

Small

Gpu opt scan outputs different dtypes rebased

Rebase fix grad

Fixes for tests with --batch option

This is to avoid confusion / conflict with the --verbose option of
nosetests.

I checked and all is fine with this remove.

* Tests of `trunc` and `trunc_inplace` Ops were testing `floor` instead
  of `trunc`.

* Inplace test for `conj` was using the non inplace version of `conj`.