Add jq_report_error() function; use it

    Put a stop to fprintf(stderr, ...) where we shouldn't.
Add JV_ARRAY() macro
Add JV_OBJECT() macro
Add `module` directive, `modulemeta` builtin

    Fix #425.
Document module system

    Fix #511.
BSD sed lacks -r; fix #551
Drop "any/" in module search; use 1.x-master
Quiet warning about freopen() of stdout