Added some information in README.md

README.md

- 
+## Purpose
+
+The RoboFish Track Format serves as an interface specification so that (1) all components of the RoboFish system can exchange tracking data in a standardized format and (2) to facility exchange of organism tracking data between researchers.
+
+## Specification
+
+Released versions can be found [here](https://git.imp.fu-berlin.de/bioroboticslab/robofish/track_format/-/releases).
+
+## Implementation(s)
+
+ - The reference Python implementation is available as [robofish.io](https://git.imp.fu-berlin.de/bioroboticslab/robofish/io).
+
 ## LICENSE
 
 This work is licensed under GPL 3.0 (or any later version).