fixup-features noisy output

fixup-features produces a lot of output, even when it finds no issues. The release technician then has to comb through the output for problems, which is quite error-prone.

For example, if you git checkout arti-v1.2.6 and run fixup-features on the top-level Cargo.toml, the output looks like this:

in fslock-guard
in hashx
in equix
in tor-basic-utils
in tor-async-utils
in caret
in fs-mistrust
in safelog
in retry-error
in tor-error
in tor-config
in tor-units
in tor-geoip
in tor-rtcompat
in tor-rtmock
in tor-log-ratelim
in tor-rpcbase
in tor-memquota
in tor-llcrypto
in tor-protover
in tor-bytes
in tor-hscrypto
in tor-socksproto
in tor-checkable
in tor-cert
in tor-linkspec
in tor-cell
in tor-proto
in tor-netdoc
in tor-consdiff
in tor-netdir
in tor-relay-selection
in tor-persist
in tor-chanmgr
in tor-ptmgr
in tor-guardmgr
in tor-circmgr
in tor-dirclient
in tor-dirmgr
in tor-keymgr
in tor-hsclient
in tor-hsservice
in tor-hsrproxy
in arti-client
in arti-relay
in arti-rpcserver
in arti
in arti-rpc-client-core
keygen-openssh-test: No version found for dependency on "tor-basic-utils"
keygen-openssh-test: No version found for dependency on "tor-keymgr"
keygen-openssh-test: No version found for dependency on "tor-llcrypto"
connection-checker: No version found for dependency on "arti-client"
connection-checker: No version found for dependency on "tor-error"
connection-checker: No version found for dependency on "tor-rtcompat"
dns-resolver: No version found for dependency on "arti-client"
obfs4-checker: No version found for dependency on "arti-client"
obfs4-checker: No version found for dependency on "tor-chanmgr"
obfs4-checker: No version found for dependency on "tor-error"
obfs4-checker: No version found for dependency on "tor-guardmgr"
obfs4-checker: No version found for dependency on "tor-proto"
obfs4-checker: No version found for dependency on "tor-rtcompat"
pt-proxy: No version found for dependency on "tor-chanmgr"
pt-proxy: No version found for dependency on "tor-linkspec"
pt-proxy: No version found for dependency on "tor-ptmgr"
pt-proxy: No version found for dependency on "tor-rtcompat"
pt-proxy: No version found for dependency on "tor-socksproto"
hyper-http-client-example: No version found for dependency on "arti-client"
hyper-http-hs-example: No version found for dependency on "arti-client"
hyper-http-hs-example: No version found for dependency on "safelog"
hyper-http-hs-example: No version found for dependency on "tor-cell"
hyper-http-hs-example: No version found for dependency on "tor-hsservice"
hyper-http-hs-example: No version found for dependency on "tor-proto"

I think an easy way to fix this would be only println!("in {}", self.name); for the crates where we have warnings to report. We should also exclude the examples.