Merge pull request #627 from knnniggett/zmu

Output to stderror when zmu can't read zm.conf

Simple enough.

src/zmu.cpp

@@ -138,6 +138,12 @@ bool ValidateAccess( User *user, int mon_id, int function )
 
 int main( int argc, char *argv[] )
 {
+	if ( access(ZM_CONFIG, R_OK) != 0 )
+	{
+		fprintf( stderr, "Can't open %s: %s\n", ZM_CONFIG, strerror(errno) );
+		exit( -1 );
+	}
+
 	self = argv[0];
 
 	srand( getpid() * time( 0 ) );