Clarification about SemVer vs ApiVer in the Readme

README.md

@@ -160,6 +160,8 @@ docker run --rm -v b2:/root -v /home/user/path/to/data:/data backblazeit/b2:late
 When you start working with `b2`, you might notice that more than one script is available to you.
 This is by design - we use the `ApiVer` methodology to provide all the commands to all the versions
 while also providing all the bugfixes to all the old versions.
+Each `ApiVer` version will match a specific `SemVer` version with the same major number.
+Thus, `ApiVer` marked as `3` will have the same behavior as the `SemVer` version `3` had.
 
 If you use the `b2` command, you're working with the latest stable version.
 It provides all the bells and whistles, latest features, and the best performance.