Firmware Folder gets removed

[ahaggard2013]

Hi,

When I run this tool at some point the unzipped Firmware folder gets wiped after extraction. This causes the "devicetree" var to be null and crash on the call to "min" on line 357 of "make_telnet_rd.php". I was able to fix it by manually unzipping the ipsw and running the script again which lets the Firmware folder persist. Not sure why the Firmware folder gets wiped, but opening an issue incase anyone runs into the same thing or feels like investigating further.