* add ndjson fuzzer
* reproduce #1310 in the newly added unit test
Had to replace the input, because:
1)
the fuzzer uses the first part of the input to determine
the batch_size to use, so that has to be cut off
2)
the master now protects against low values of batch_size
I also made the test not return early, so the error is triggered.
* add definitions for is_number and tie (by lemire)
* add fuzzer for element
* update fuzz documentation
* fix UB in creating an empty padded string
* don't bother null terminating padded_string, it is done by the std::memset already
* refactor fuzz data splitting into a separate class
This adds a fuzzer for at_pointer() which recently had a bug.
The #1142 bug had been found with this fuzzer
Also, it polishes the github action job:
cross pollinate the fuzzer corpora (lets fuzzers reuse results from other fuzzers)
use github action syntax instead of bash checks
only run on push if on master
Paul Dreik