message: fix "unused" import warning on non-linux targets
diff: @@ -11,7 +11,6 @@ use crate::utils::{copy_doc_dir, parse_rustc_version, CargoMetadata, GithubUpdat
  use crate::{db::blacklist::is_blacklisted, utils::MetadataPackage};
  use crate::{Config, Context, Index, Metrics, Storage};
  use docsrs_metadata::{Metadata, DEFAULT_TARGETS, HOST_TARGET};
  -use failure::bail;
  use failure::ResultExt;
  use log::{debug, info, warn, LevelFilter};
  use postgres::Client;
  @@ -320,7 +319,7 @@ impl RustwideBuilder {
  .mem_available
  .expect("kernel version too old for determining memory limit");
  if limits.memory() as u64 > available {
  - bail!("not enough memory to build {} {}: needed {} MiB, have {} MiB\nhelp: set DOCSRS_DISABLE_MEMORY_LIMIT=true to force a build",
  + failure::bail!("not enough memory to build {} {}: needed {} MiB, have {} MiB\nhelp: set DOCSRS_DISABLE_MEMORY_LIMIT=true to force a build",
  name, version, limits.memory() / 1024 / 1024, available / 1024 / 1024
  );
  } else {
  