Answer: Yes the /linoma/goanywhere/tomcat/logs can be deleted. There are a number of different logs in the tomcat directory: admin.2008-2-15, catalina.2008-2-15, etc. The file catalina.out file does not roll over and can get rather large. The file cannot be deleted or renamed while the GoAnywhere subsystem or service is running.
You can create a GoAnywhere project to work with the logs, rename, delete etc for all the logs except catalina.out. The project could include a task to check the size of catalina.out and notify someone to rename it when it reaches a certain size. The renamed file can then be archived or deleted. A new catalina.out will be created automatically when the GoAnywhere subsystem or services is restarted.
How long you should keep them is really up to you. All the files except catalina.out can be deleted as soon as they roll over.