fix not checking for unrar

[nn9dev]

i ran this for like 30 mins before i realised that i didn't have unrar installed. hopefully this helps people in the future.

[nn9dev]

nah travis hates me. i think it's a problem with 7z but i dunno

[jaredsburrows]

@nn9dev I believe you are almost there. It looks like 7z passed but now zip files fail?

[nn9dev]

if I was able to tell you what the error was here, i'd be all over it. I honestly do NOT know. if travis was more verbose when running commands and such then MAYBE but I have no idea what's up

[jaredsburrows]

Have you tried running your code locally? Then running the commands that travis is running locally?

[nn9dev]

It works perfectly fine on my end. I noticed in the Travis build that it doesn't either throw a confirm or an error for the 7z bit of code and so I made it return EXEC_FAILURE which maybe I shouldn't have done because if someone is trying to do a rar and doesn't have 7z then it just halts so maybe I'll revise that but if you can see a way to fix it on Travis I could try to fix that if you see it as necessary