pull: skip editor if changes were explicitly passed

Dependencies

• [2] MU5GSJAW Partial push and pull (WARNING: breaks the existing protocol)
• [3] SXEYMYF7 Fixing the bad changes in history (unfortunately, by rebooting).
• [4] M5FK3ABT Complete dependencies when pushing and pulling
• [5] BBKV6VMN Fixing push/pull messages, and do not reverse the changes to download/upload
• [6] X6YFD4WV Do not download changes if we already have them

Change contents

• replacement in pijul/src/commands/pushpull.rs at line 433
  [2.10157]→[3.120122:120145](∅→∅),[3.120122]→[3.120122:120145](∅→∅)
  − if !self.all {
  [2.10157]

  [3.146]
  + if !self.all && self.changes.is_empty() {