Change the runner behavior

[louismerlin]

The runner binary now only runs a single file given as argument. Ziggy handles the directory exploration, and has an option to either stop if a crash is found, or continue running inputs (default).

cargo ziggy run -i path/to/corpora/      # executes all files and does not stop on a crash
cargo ziggy run -x -i path/to/corpora/   # executes files and stops if a crash is found
# You can also use the `-r` flag for recursion

• Move the file-discovery code from the runner harness to cargo-ziggy
• Create the -x flag
• Make sure the coverage generates even if there are crashes in the corpora
• Removed unimplemented -G flag for max input length

[vanhauser-thc]

why -x? 'S' or 'C' might be more intuitive maybe? also what about timeouts?

[louismerlin]

-x kind of looks like a line crashing 😄 I'm open to changing it to -C.

ziggy run reacting to timeouts is a good idea, I'll create an issue 👍