[v1.x] Tool to help update/restore onnx support

[Zha0q1]

As we frequently improve our ONNX support, users might want to get timely access to the latest changes. However, MXNet releases might not happen as frequent as the users would want and they might have other compatibility concerns to update the entire mxnet module. To help with this, this pr adds a simple tool to update(replace) and restore the mxnet/contrib/onnx folder to the latest version on github. For example, a user that has mxnet 1.7 installed can use this script to get the latest onnx support without updating mxnet to a later version. This script helps make our onnx support more accessible and users can report bugs back and expect them fixed more easily.

The script will automatically find the currently installed mxnet. The original files will be backuped to mxnet/contrib/onnx/backup. --branch option controls which mxnet branch to checkout and if --restore option is specified then files in backup will be restored.

To update to changes in v1.x

python update_onnx.py

To update to changes in a specific branch

python update_onnx.py --branch <branch>

To restore the original files

python update_onnx.py --restore

[mxnet-bot]

Hey @Zha0q1 , Thanks for submitting the PR All tests are already queued to run once. If tests fail, you can trigger one or more tests again with the following commands:

• To trigger all jobs: @mxnet-bot run ci [all]
• To trigger specific jobs: @mxnet-bot run ci [job1, job2]

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CI supported jobs: [windows-cpu, website, clang, centos-cpu, windows-gpu, centos-gpu, edge, unix-gpu, unix-cpu, miscellaneous, sanity]

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Note: Only following 3 categories can trigger CI :PR Author, MXNet Committer, Jenkins Admin. All CI tests must pass before the PR can be merged.