Some packages were using `logrus.Fatal()` in init functions (which logs the error,
and (by default) calls `os.Exit(1)` after logging).
Given that logrus formatting and outputs have not yet been configured during the
initialization stage, it does not provide much benefits over a plain `panic()`.
This patch replaces some instances of `logrus.Fatal()` with `panic()`, which has
the added benefits of not introducing logrus as a dependency in some of these
packages, and also produces a stacktrace, which could help locating the problem
in the unlikely event an `init()` fails.
Before this change, an error would look like:
$ dockerd
FATA[0000] something bad happened
After this change, the same error looks like:
$ dockerd
panic: something bad happened
goroutine 1 [running]:
github.com/docker/docker/daemon/logger/awslogs.init.0()
/go/src/github.com/docker/docker/daemon/logger/awslogs/cloudwatchlogs.go:128 +0x89
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
df650a1aeb