Many codecs can take a huge amount of time attempting to read large
random objects. jpeg_read_header(), for example, can take ~10s on a 1mb
of random data.
Ignore fuzz objects over 100kb.
See https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=24383
It replaces current fuzz setup with 5 new fuzzers integrating them with
top-level Makefile. It now supports multiple fuzzing engines and Google's
oss-fuzz. By default, the fuzzers are linked against an standalone runner to
easily reproduce bugs.