Merge bitcoindevkit/bdk#1290: doc(example_cli): add missing cli docs

Merge bitcoindevkit/bdk#1290: doc(example_cli): add missing cli docs

c4d5f2ccd8435b9c424eec5ba35ba44a3383b04d doc(example_cli): add missing cli docs (vmammal)

Pull request description:

  ### Checklists

  #### All Submissions:

  * [x] I've signed all my commits
  * [x] I followed the [contribution guidelines](https://github.com/bitcoindevkit/bdk/blob/master/CONTRIBUTING.md)
  * [x] I ran `cargo fmt` and `cargo clippy` before committing

ACKs for top commit:
  evanlinjin:
    ACK c4d5f2ccd8435b9c424eec5ba35ba44a3383b04d

Tree-SHA512: 43684abbb32570f07e0dc05ed07062bc7969cbe7c4fefe8ae7ebe41ac28aedfbba76ffc801bc4ddb3bf08a940ca81c128376dc3f6c76a04f1391e43c18e0d50b