Return settings from parse_args as struct sudo_settings and format

for the plugin at plugin open time.  This will allow for additional,
plugin-specific settings to be added to the array.

src/sudo.h

@@ -85,6 +85,12 @@
 #define TGP_MASK	0x08		/* mask user input when reading */
 #define TGP_NOECHO_TRY	0x10		/* turn off echo if possible */
 
+/* name/value pairs for command line settings. */
+struct sudo_settings {
+    const char *name;
+    const char *value;
+};
+
 struct user_details {
     pid_t pid;
     pid_t ppid;
@@ -186,7 +192,7 @@ int sudo_execute(struct command_details *details, struct command_status *cstat);
 
 /* parse_args.c */
 int parse_args(int argc, char **argv, int *nargc, char ***nargv,
-    char ***settingsp, char ***env_addp);
+    struct sudo_settings **settingsp, char ***env_addp);
 extern int tgetpass_flags;
 
 /* get_pty.c */