Max size for all session log files increased to a total of 2GB

Currently: Session log files are deleted oldest first once they reach a certain number of files (10). Additionally, a new sessionlog file is created if the current is more than 100MB in size. These two facts together means that you will never run out of disk space, which is critical for manufacturing.

Changes: Total number of session files raised to 20, keept 100MB individual size before splitting (total filesize for all log files will not exceed 2GB).