Logfetch 0.20.0

Updates to usage of cached files

• Be smarter about when to use cached files for live logs by checking:
  • If it's a zipped file, it probably hasn't changed, use the cache
  • If the task is not in a running state, and the cached file was downloaded after the task finished, use the cached file
• Add a -U / --use-cache option to prefer the cached version of a live log file instead of re-downloading it no matter what the task state or age of the cached file is
• Add a logsearch command as an offline way of searching through files in the cache directory, also available by adding --search to the logfetch command