This patch adds the tag "signed" to messages with any multipart/signed
parts, and the tag "encrypted" to messages with any
multipart/encrypted parts. This only occurs when messages are indexed
during notmuch new, so a database rebuild is required to have old
messages tagged.
Change #!/bin/bash at start of tests to "#!/usr/bin/env bash". That way
systems running on bash < 4 can prepend bash >= 4 to path before
running the tests.
This testing *does* capture the bug of missing '[' and ']' characters
int "notmuch search --output=tags" case. This is another manifestation
of the same bug causing the missing final newline (as mentioned in the
previous commit).
This code simply wasn't being exercised by the test suite before, so
this will be useful.
Meanwhile, there's currently a bug in "notmuch search --output=tags"
in that it doesn't print a final newline. But the current test suite
isn't able to catch this bug since the $() construct of the shell
doesn't preserve the distinction of whether the final newline is
present or not.
