Updating-and-release-notes.md

-### Current version: `3.0.0-beta9`
+### Current version: `3.0.0-beta10`
 
 You can check the version installed by running `obi --version`
 
 ### Release notes:
 
+* `3.0.0-beta10`: `obi import`: new option --preread to do a first readthrough of the
+dataset if it contains huge dictionaries for a much faster import.
+
 * `3.0.0-beta9`: Better disk space management when importing files (rewritten columns are deleted).
 
 * `3.0.0-beta8`: Fixed a bug when importing a file where the first entry would contain a dictionary with a single key.