## Changes
This PR adds a library for spawning a daemon process. Our needs are
different from those of a typical daemon process in that we want to
handle being orphaned gracefully. This is because, in the vast majority
of telemetry use cases, the main CLI process (i.e., the parent process)
will exit before the telemetry process has a chance to finish uploading
the logs.
To achieve this we "detach" the child process from the parent process,
which requires different flags for UNIX vs. non-unix systems.
Here are the properties that we want to ensure for our telemetry
child/daemon processes:
1. They do not block the parent process.
Reason: The main CLI process should not be blocked on the telemetry
child process.
2. The child can read from stdin. The parent can write to stdin.
Reason: Telemetry logs will be passed to the child process via stdin.
3. Output logs do not leak from the child process.
Reason: Telemetry logs should not be visible to users of the CLI.
## Tests
Unit test
ddcfac5069