Delayed-image

Fixed:
* Half of the off-by-one bug, the other half seems to be from align corners.

Changed
* Small speedups

Changed

* modified the signature of `DelayedLoad.demo` to better match `__init__` and
`grab_image_test_fpath`.

Fixed

* floating point bug where an overview would fail to be absorbed into a warp.

Fixed
* Issue in SensorChan spec where duplicate sensors were present in concise codes

Added
* Added `__json__` to sensorchan specs
* Added `resize` method

Fixed
* A Dequantize node between a warp and and overview now has its size modified correctly.

Changed
* `write_network_text` now defaults to rich='auto'

Changed
* 3.6 support

Added
* new method `get_transform_from` which returns the transform from the space of
one delayed image to the space of another.

Changed
* Added `noop_eps` parameter to delayed warp, which will optimize it away if
the warp is close to identity.

Fixed
* Fixed issue where warp parameters would not be carried through.