Add support for Billion / Telewell devices

[GoogleCodeExporter]

Please investigate the work previously done by Finnish hacker Harry Sintonen 
considering the violations of GPL by Telewell and Billion (same devices, 
rebranding):

https://www.sintonen.fi/telewell_gpl/

Especially, read https://www.sintonen.fi/telewell_gpl/readme.txt, 
https://www.sintonen.fi/telewell_gpl/gpl_components_in_firmware.txt and 
https://www.sintonen.fi/telewell_gpl/gpl_components_in_firmware2.txt.

Sintonen provides public domain source code for extracting these firmwares 
(cramfs and kernel).

Thanks to Sintonen, Telewell has provided (at least almost) everything required 
to build the firmware:
https://www.telewell.fi/edistyneille/

Billion has also provided some source packages, e.g.: 
http://au.billion.com/downloads/usermanual/wireless/PCRange-7300GA-V1.35-RC8-180
-80.3.tar.gz, 
http://au.billion.com/downloads/firmware/wireless/PCRange7800NL.rar, 
http://au.billion.com/downloads/firmware/3g-adsl2+/7800GZ_1.04a_PCRange.tar.gz, 
http://au.billion.com/downloads/firmware/wireless/7300N_1.06g_PCRange.tar.gz. 
Could issue 93 also be solved with these?

Downloading the links on that page will give you the sources + toolchains. I've 
managed to build the firmware package from sources for TW-EA510 v3. The process 
is quite straight forward, but will most likely require a few Makefile changes 
(sed path etc). 

As Sintonen provides working code for extracting the firmware and the method 
for packaging the firmware is included in the toolchain, this should be quite 
easy task for you?

If you are willing to act on this, I've got a TW-EA510 v3 (b) and a TTL serial 
for testing purposes. However, this specific firmware 
(https://telewell.fi/files/paivitystiedostot/Telewell-510v3b-1_08a_dj5-A_afw.zip
) is not being fully understood by Sintonen's tools as only the kernel image is 
extracted by scangzip.

Original issue reported on code.google.com by joe.ka...@gmail.com on 10 Jul 2013 at 10:52