Add precedence info to manpage & fix noblacklist example

src/man/firejail.1.in

@@ -96,6 +96,13 @@ $ firejail [OPTIONS] firefox        # starting Mozilla Firefox
 .PP
 # sudo firejail [OPTIONS] /etc/init.d/nginx start
 
+When an option is specified multiple times (whether in a profile, on the
+command line, or both) or conflicts with a related option, the
+precedence/behavior is option-specific and usually documented in the
+\fBOPTIONS\fR section below. Note that any option specified in a profile can be
+disabled on the command line using \fB--ignore\fR.
+
+
 .SH OPTIONS
 .TP
 \fB\-\-
@@ -1729,6 +1736,10 @@ See --keep-config-pulse.
 Disable blacklist for this directory or file.
 .br
 
+Note that this only applies to the path as written when it was blacklisted,
+including unexpanded variables and wildcards.
+.br
+
 .br
 Example:
 .br
@@ -1744,6 +1755,14 @@ $ exit
 .br
 $ firejail --noblacklist=/bin/nc
 .br
+bash: /bin/nc: Permission denied
+.br
+$ exit
+.br
+
+.br
+$ firejail --noblacklist='${PATH}/nc'
+.br
 $ nc dict.org 2628
 .br
 220 pan.alephnull.com dictd 1.12.1/rf on Linux 3.14-1-amd64