v0.11.0

Stable-channel republication of 1.0.0-rc.3. The code is the rc's code with a
stable version stamp, so users who have not opted into prereleases get the
fixes. See the 1.0.0-rc.3 entry for detail.

Breaking (relative to 0.10.0)

• enabled is now isEnabled() on tracers, loggers and instruments, and the
  enabled constructor parameter is removed. Replace x.enabled with
  x.isEnabled().
  (#105)
• getTracer, getLogger and getMeter no longer invent a scope version or
  schema URL. Both are null when you omit them.
  (#108)