The file format for each option now features a "Example:" header that
can provide one or more examples that get rendered appropriately in the
output. All options MUST have at least one example or gen.pl complains
at build-time.
This fix also does a few other minor format and consistency cleanups.
Closes#7654
The command line tool also independently sets --ftp-skip-pasv-ip by
default.
Ten test cases updated to adapt the modified --libcurl output.
Bug: https://curl.se/docs/CVE-2020-8284.html
CVE-2020-8284
Reported-by: Varnavas Papaioannou
