Update bench_tester.py

1. Addresses are re-read from files of addresses every iteration (every attack) because they can change. Before there were read once and then attack started. Now every new attack with every new run of a vulnerable app  re-reads the addresses in the while-loop
2. Function readAddresses(aslr_mode, attackmode) added to read addresses from files, generated by vulnerable apps. This function is called with every new run of an attack inside while lool
3. attack_mode is now taken into consideration when building malicious input string. In mode 1 we try to jump to the shell. In mode 0 we try to jump into malicious program 'indicator'
4. File 'indaddress' is now parsed to get an address of a malicious program 'indicator' in hex-format
5. In the initialization section file 'indaddress' is created, which contains the default address of a malicious program 'indicator'
6. Attacking command for polymorph added: it requires additional option "-f": 
    $ polymorph -f "malicious string"