Proper renaming of changes downloaded over HTTP

Dependencies

• [2] VBMXB443 Retrying if the HTTP connection drops while reading the body
• [3] IQ4FCHPZ HTTP connections: pooling + retry on error
• [*] FBXYP7QM Forgot to add remote::http

Change contents

• replacement in pijul/src/remote/http.rs at line 31
  [3.578]→[2.56:75](∅→∅)
  − 'outer: loop {
  [3.578]

  [2.75]
  + loop {
• replacement in pijul/src/remote/http.rs at line 48
  [3.1193]→[2.241:256](∅→∅)
  − loop {
  [3.1193]

  [2.256]
  + let done = loop {
• replacement in pijul/src/remote/http.rs at line 54
  [2.448]→[2.448:490](∅→∅)
  − Ok(None) => break 'outer,
  [2.448]

  [2.490]
  + Ok(None) => break true,
• replacement in pijul/src/remote/http.rs at line 59
  [2.719]→[2.719:746](∅→∅)
  − break;
  [2.719]

  [2.746]
  + break false;
• edit in pijul/src/remote/http.rs at line 62
  [2.778]

  [2.778]
  + };

  + if done {

  + std::fs::rename(&path_, &path_.with_extension("change"))?;

  + break;
• edit in pijul/src/remote/http.rs at line 67
  [2.788]→[2.788:855](∅→∅)
  − std::fs::rename(&path_, &path_.with_extension("change"))?;