CLI, debian, make: misc cleanup and changes (#336)

This PR	groups misc cleanup and changes from https://github.com/ooni/probe-cli/pull/331.

* CLI/linux/build: add documentation

* debian/.gitignore: ignore generated files

* debian/TODO: unnecessary at this point

* debian/ooniprobe-cli.service: remove commented out lines

* debian/rules: remove unnecessary actions

* make: reindent and fix spelling

* smoketest.sh: don't run in verbose mode

Part of https://github.com/ooni/probe/issues/1466

debian/ooniprobe-cli.service

@@ -1,7 +1,6 @@
 [Unit]
 Description=OONI Probe CLI
 Documentation=man:ooniprobe-cli
-#Documentation=file:///usr/share/doc/ooniprobe-cli/html/index.html
 Documentation=https://ooni.org/
 After=network.target tor.target
 Wants=network-online.target
@@ -22,7 +21,6 @@ LimitNOFILE=65536
 WorkingDirectory=/var/lib/ooniprobe
 RuntimeDirectory=ooniprobe
 StateDirectory=ooniprobe
-#CacheDirectory=ooniprobe
 LogsDirectory=ooniprobe
 ConfigurationDirectory=ooniprobe