Ingest

Initial working version of ingestion. Originally put in another repo but recreated here since this is where the code will be hosted from now on. In order for this PR to work though, I had to manually copy things over which lost the old commit history though luckily there wasn't that much.

freva/src/drs/ingest.rs

@@ -170,14 +170,12 @@ async fn ingest_structure(
 
             let f = Arc::new(f);
             if let Some(version) = f.version() {
-                // TODO: we need proper data set versioning
-                let version = version.to_owned();
                 let id = f.to_unversioned_identifier();
 
                 match latest_versions.get_mut(&id) {
                     Some(latest) => {
-                        if version.as_str() >= latest.as_str() {
-                            *latest = version;
+                        if version >= latest.as_str() {
+                            *latest = version.to_owned();
                             latest_buf.push(f.clone());
                         }
                     }