tlog is used heavily everywhere and deserves a shorter name.
Renamed using sed magic, without any manual rework:
find * -type f -exec sed -i 's/toggledlog/tlog/g' {} +
Several fatal errors were just printed to stdout, which
meant they were invisible when running the test suite.
Fix this by introducing toggledlog.Fatal and convert as
follows:
Fatal errors -> toggledlog.Fatal
Warnings -> toggledlog.Warn
Password prompts -> fmt.Fprintf
Instead of using SetOutput(ioutil.Discard), which means
that Printf is still called for every debug message,
use a simple and fast boolean check.
Streaming write performance improves from 86 to 93 MB/s.
