Add implementation of `conv1d_transpose` (#13105)

* Add implementation of `conv1d_transpose`

This fix tries to address the issue raised in 8729 by
providing the implementation of `conv1d_transpose`.

This fix fixes 8729.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

* Add test case for `conv1d_transpose`

This fix adds test case for `conv1d_transpose`.

This fix is related to 8729.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

* Fix xrange issue in Python 3

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

* Change allowed data format from `NHWC`/`NCHW` -> `NWC`/`NCW`

as 1d does not have height.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

* Expose conv1d_transpose from tf.contrib.nn

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>