Add Example service; Nitpick comments

Hopefully the example config will be helpful for somebody trying to
understand how to use this.
2 jobs from dependencies in 2 minutes and 12 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Build
failed #8396
allowed to fail
build:linux:cargo

00:01:37

passed #8397
build:redox:cargo

00:02:12

 
Name Stage Failure
failed
build:linux:cargo Build

error: aborting due to 7 previous errors

For more information about this error, try `rustc --explain E0308`.
error: Could not compile `init`.

Caused by:
process didn't exit successfully: `rustc --edition=2018 --crate-name init src/main.rs --color never --crate-type bin --emit=dep-info,link -C debuginfo=2 -C metadata=6991ef85a6d0164d -C extra-filename=-6991ef85a6d0164d --out-dir /builds/redox-os/init/target/debug/deps -C incremental=/builds/redox-os/init/target/debug/incremental -L dependency=/builds/redox-os/init/target/debug/deps --extern chashmap=/builds/redox-os/init/target/debug/deps/libchashmap-9fc602786a47b039.rlib --extern colored=/builds/redox-os/init/target/debug/deps/libcolored-f056e50516d76f21.rlib --extern failure=/builds/redox-os/init/target/debug/deps/libfailure-80e619ea2cce25b0.rlib --extern fern=/builds/redox-os/init/target/debug/deps/libfern-b393b791c3cda155.rlib --extern generational_arena=/builds/redox-os/init/target/debug/deps/libgenerational_arena-0765194bb300a825.rlib --extern latest=/builds/redox-os/init/target/debug/deps/liblatest-3885a3faa5fa18b9.rlib --extern log=/builds/redox-os/init/target/debug/deps/liblog-b16886b05d6d6435.rlib --extern syscall=/builds/redox-os/init/target/debug/deps/libsyscall-8ea74aab5d711db4.rlib --extern redox_users=/builds/redox-os/init/target/debug/deps/libredox_users-86396268bb3e0d6d.rlib --extern serde=/builds/redox-os/init/target/debug/deps/libserde-f64b7453b6620be4.rlib --extern serde_derive=/builds/redox-os/init/target/debug/deps/libserde_derive-da6c4b0b67e56cff.so --extern toml=/builds/redox-os/init/target/debug/deps/libtoml-857d55070176fb14.rlib -L native=/builds/redox-os/init/target/debug/build/backtrace-sys-751fef5f0a7686ee/out` (exit code: 1)
ERROR: Job failed: exit code 1