Filters can now indicate a status back to cgit by means of the exit code
for exec, or the return value from close for Lua.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Since the email filter is called from lots of places, the script might
benefit from knowing the origin. That way it can modify its contents
and/or size depending.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
