Switch from using hdiutil to parsing the iso file directly.

[dlorenc]

I'm still not completely happy with this code, but I wanted to send it out early and see what you thought @zchee.

[zchee]

@dlorenc Thanks. I know iso9660 package (but was not digging), it's make sense.
Some users waiting to release the new version and pre-build binary. I'll check that package and test this pull request after the release new version. #182

[zchee]

@dlorenc

I'm still not completely happy with this code

OK, I'll wait for the complete code.
Could you rebase to master(for now)? Maybe CI test is successful.

[zchee]

and, /cc @praveenkumar because he wrote the related code.

[praveenkumar]

Thanks for notification, I will go through it and test.

[praveenkumar]

Tested this PR with CentOS/b2d iso and it able to extract kernel options as expected. 👍

[zchee]

@dlorenc This PR and #189, Which is a priority?

[dlorenc]

#189, I'll rebase this one after :)