Update documentation to cover daemon tests

doc/testing.md

@@ -8,27 +8,31 @@ feed some input to GPG Mailgate and inspect the output.
 
 To run tests, use command `make test`.
 
-There are 3 types of tests:
+There are 4 types of tests:
 
   * `make e2etest` -- they cover a complete Lacre flow, from feeding it with
     an email to accepting its encrypted form;
+  * `make daemontest` -- similar to the original `e2etest` goal, but tests the
+    behaviour of the Lacre Daemon, i.e. key part of the Advanced Content
+    Filter.
   * `make unittest` -- just small tests of small units of code;
-  * `make crontest` -- execute cron job with a SQLite database.
+  * `make crontest` -- execute cron job with a SQLite database.
 
 E2E tests (`make e2etest`) should produce some helpful logs, so inspect
 contents of `test/logs` directory if something goes wrong.
 
 If your system's Python binary isn't found in your `$PATH` or you want to use
-a specific binary, use make's macro overriding: `make test
+a specific binary, use make's macro overriding: `make test
 PYTHON=/path/to/python`.
 
 ## Key building blocks
 
-- *Test Script* (`test/e2e_test.py`) that orchestrates the other components.
-  It performs test cases described in the *Test Configuration*.  It spawns
-  *Test Mail Relay* and *GPG Mailgate* in appropriate order.
-- *Test Mail Relay* (`test/relay.py`), a simplistic mail daemon that only
-  supports the happy path.  It accepts a mail message and prints it to
+- *Test Script* (`test/e2e_test.py`) and *Daemon Test Script*
+  (`test/daemon_test.py`) that orchestrate the other components.  They perform
+  test cases described in the *Test Configuration*.  They spawn *Test Mail
+  Relay* and *GPG Mailgate* in appropriate order.
+- *Test Mail Relay* (`test/relay.py`), a simplistic mail daemon that only
+  supports the happy path.  It accepts a mail message and prints it to
   stdandard output.
 - *Test Configuration* (`test/e2e.ini`) specifies test cases: their input,
   expected results and helpful documentation.  It also specifies the port that
@@ -38,7 +42,7 @@ PYTHON=/path/to/python`.
 
 Currently tests only check if the message has been encrypted, without
 verifying that the correct key has been used.  That's because we don't know
-(yet) how to have a reproducible encrypted message.  Option
+(yet) how to have a reproducible encrypted message.  Option
 `--faked-system-time` wasn't enough to produce identical output.
 
 ## Troubleshooting