Document "--replace" better

This adds it to the output of "awesome -h" and translates the version in the man
page to italian. Thanks, eri_trabiccolo for the translation!

Signed-off-by: Uli Schlachter <psychon@znc.in>

awesome.c

@@ -418,7 +418,8 @@ exit_help(int exit_code)
   -h, --help             show help\n\
   -v, --version          show version\n\
   -c, --config FILE      configuration file to use\n\
-  -k, --check            check configuration file syntax\n");
+  -k, --check            check configuration file syntax\n\
+  -r, --replace          replace an existing window manager\n");
     exit(exit_code);
 }
 

manpages/awesome.1.it.txt

@@ -53,7 +53,7 @@ OPZIONI
 *-a*, *--no-argb*::
 	Non usare visuali ARGB.
 *-r*, *--replace*::
-	Replace an existing window manager.
+	Sostituisci un gestore di finestre esistente.
 
 DEFAULT SCORCIATOIE CON IL MOUSE
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