CY-1048 amqp_postgres: don't break on logs containing NULs (#1640)
CY-1048 amqp_postgres: don't break on logs containing NULs (#1640)

* CY-1048 amqp_postgres: treat ValueError as other data errors

When failing on inserting malformed data, also expect a ValueError to
be thrown. This can happen eg. if the values contain NUL bytes.

* amqp_postgres: remove NULs from the user-provided logs

* Change placeholder to <NUL>

cloudify-cosmo/cloudify-manager,cloudify-cosmo/cloudify-manager,cloudify-cosmo/cloudify-manager