Firmware support for linksys EA6700 firmware

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What steps will reproduce the problem?
1. Download the firmware for EA6700 router from linksys site
2. Try to dissect it with fmk
3. fmk produces rootfs, but fails to extract kernel and some other data

What is the expected output? What do you see instead?
fmk does not extract header

What version of the product are you using? On what operating system?
latest greatest version 0.99

Please provide any additional information below.

Linksys EA6700 firmware is as follows:

1-TRX header
2-LZMA-compressed image (LZMA 4.65 to uncompress)
3-JFFS rootfs

Inside 2 there is some data, couple more TRX headers, linux kernel, XZ
compressed data (extra config) and some more LZMA data

Ideally i would love to see all of that being extracted and reassembled so that
firmware can be truly modded.

Thanks a ton for the work done already on the toolset.

```

Original issue reported on code.google.com by `andlo...@gmail.com` on 31 Oct 2013 at 1:42

Start with the fmk extraction path using the supplied Linksys EA6700 firmware and compare its handling of the outer TRX header and nested LZMA, JFFS, kernel, XZ, and additional LZMA data. No source files or tests are named in the issue. Done means the relevant contents are extracted and the firmware can be reassembled for modification.

Written by the indexing model from the issue text.