Added duration calculation (TODO: fix for wrap-around cases)
Use date command to do duration calculation through some sneakiness
Refactored and made into infinite loop
refactor formatting into external variables
Added another env var for previously recorded entries
Added trap_func for saving before quit
Added file touching at start
Now saves format strings in the file
Now does FORMAT_ENTRY dollar sign escaping inline instead of with sed
Now saves actual ENTRIES array to file as well
Now puts current entry into the entry array