Better way of handling the existing file check

[Flozza]

Currently, when a user can/does not provide an exploit like this

./exploit

and instead uses something like this

php -f exploit.php

he can not use the file check feature. Since this is turned on by default, this causes a lot of confusion. This option should be disabled by default or we have to find another sane way of checking for an existing file.

[Flozza]

@fluxchief Do you have an idea on this? Our web UI solves this to some degree: It disables this on Windows and we might even add something that disables it if it does not start with ./ but this does not seem nice. Is there a good way to detect this?

By the way the most important thing is that we check for a shebang where we can, it caused a lot of confusion and weird errors no one could explain when it was missing.