Fixed nc no longer running after 1 single connection in SSRF lab.
Consistency in use of spaces instead of tabs.
Changed static IP of CORS to localhost so it will work more consistently.
Added installation instructions for imagemagick on Linux for cmd injection lab.
Slightly refactored PDF generation function in IDOR lab to be a bit more readable (the while implied that 1500 documents would be generated, while only one would be).
Changed IDOR lab to run from 500 instead of 1500. This makes it easier to do when the Community edition of Burp Intruder is used (it's slooooooow).
Small change in error handling (dictionary vs string) in yaml deserialisation lab.