makepdf.sh: some fixes

makepdf.sh

-#!/bin/sh
+#!/bin/bash
 if [ $# -lt 1 ]; then
         echo "USAGE: ./makepdf.sh [--fsr] protokoll.{md|txt|...}"
         exit 1
 fi
-if [ "$1" == "--fsr" ]; then
+if [ "$1" = "--fsr" ]; then
     F="fsr"
 else
     F="finf"