trace-tef: add a ticker thread to ensure we flush the file regularly
0.2
trace-tef: additional argument to with_setup; env for "stdout"/"stderr"
refactor: avoid conflicting with stdlib Trace module by adding sublibrary trace.core. Programs that use compiler-libs.toplevel should use trace.core directly, because using trace will cause linking errors.
perf(trace-tef): improve behavior of collector under contention by pulling all events at once in the worker