Clean up the text a bit

docker-compose.env.example

@@ -21,16 +21,17 @@ PAPERLESS_PASSPHRASE=CHANGE_ME
 # These values are required if you want paperless to check a particular email
 # box every 10 minutes and attempt to consume documents from there.  If you
 # don't define a HOST, mail checking will just be disabled.
-# don't use quotes after = or it will crash your docker
+# Don't use quotes after = or it will crash your docker
 # PAPERLESS_CONSUME_MAIL_HOST=
 # PAPERLESS_CONSUME_MAIL_PORT=
 # PAPERLESS_CONSUME_MAIL_USER=
 # PAPERLESS_CONSUME_MAIL_PASS=
 
-# Override the default IMAP inbox here. If not set Paperless defaults to
+# Override the default IMAP inbox here. If it's not set, Paperless defaults to
 # INBOX.
 # PAPERLESS_CONSUME_MAIL_INBOX=INBOX
 
 # Any email sent to the target account that does not contain this text will be
-# ignored.
+# ignored.  Mail checking won't work without this.
 # PAPERLESS_EMAIL_SECRET=
+