Unattended analysis and return value.

Added command line option `-q` that disables the last `getchar()` for unattended analysis.

Changed command return value to match the analysis result; with the following scheme:
 - Everything `OK` -> 0
 - Something `suspicious` but nothing `traced` -> 1
 - Something `traced` -> 2

With this changes the tool can be now used as an automatic testing tool for sandbox images.