various manpage changes
various manpage changes

- fix misspelling typo
- strftime is about --gmtime/--localtime and not -s specifically
- add a sentence about this strftime purpose
- add an example of the strftime converted filename
- mention -s in regards to splitting
- add commas in the SEE ALSO list, while there sort,
  use .BR macro instead, and put the webpage reference next to them

farsightsec/fstrm,farsightsec/fstrm