Added support for getting targets from file and stdin

[d0nutptr]

You can now specify targets using:

1. --targets (-t)

   armada -t 1.1.1.1 -p 80,443

2. --target_file

   armada --target_file ips_and_cidrs.txt -p 80,443

3. stdin

   cat ips_and_cidrs.txt | armada -p 80,443