This proposal will:
1) Accept incoming XCM/HRMP channel request from Centrifuge and Polkadex and send corresponding open channel requests back to Centrifuge and Polkadex.
2) Register CFG, PDEX, and HDX in the Acala asset registry.

I have tested this call with Chopsticks. It took about 3 hrs to create and test.

The extrinsics in this call are:
XCM message to execute on Polkadot: `0x1a00103c01ef0700003c00ef070000e8030000009001003c01f80700003c00f8070000e803000000900100`
Overall Acala call: `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`

1. This proposal will accept requests from Centrifuge and Polkadex and send corresponding requests back to them.
2. It will register CFG, PDEX, and HDX in the Acala asset registry.
3. The call has been tested with Chopsticks and took about 3 hours to create and test.
4. The call includes XCM message to execute on Polkadot.
5. The overall Acala call includes multiple extrinsics.

Accept Centrifuge, Polkadex channels. Register CFG, PDEX, HDX