Merge bitcoindevkit/bdk#1235: Refactor/rename electrum_ext and esplora_ext to have...

de54e710ed04e3cb1632cf99dbc1c6f2374b0c6e refactor(esplora_ext): rename scan_txs to sync and scan_txs_with_keychains to full_scan (Steve Myers)
95d34854f46fd154eed35008954b25b82785b2d8 refactor(electrum_ext): rename scan_without_keychain to sync and scan to full_scan (Steve Myers)

Pull request description:

  ### Description

  fixes #1112

  Simple function renaming plus updated docs:

  1. electrum_ext: rename functions `scan_without_keychain` to `sync` and `scan` to `full_scan`
  2. esplora_ext: rename functions `scan_txs` to `sync` and `scan_txs_with_keychains` to `full_scan`

  ### Notes to the reviewers

  The esplora_ext changes were partially fixed in #1070 but I renamed again so the functions match names ~~suggested in #1112~~ agreed on in discord poll, `sync` and `full_scan`.

  ### Changelog notice

  Changed

  - electrum_ext: rename functions scan_without_keychain to sync and scan to full_scan
  - esplora_ext: rename functions scan_txs to sync and scan_txs_with_keychains to full_scan

  ### 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

Top commit has no ACKs.

Tree-SHA512: d34516ecc513a194b679f73a1260d0cbc3d12b6a2e162d822e7381da0b3250aff319e85ed2fadec506e36f95a78a5cd79d0ab972da2b02928c074be17664da08