Start migrating the Developer's Guide to AsciiDoc. So far only one

Start migrating the Developer's Guide to AsciiDoc. So far only one
chapter (WSDG_chapter_sources) has been converted.

Conversion was done using the script in
https://code.wireshark.org/review/#/c/9/ along with manual cleanup.
Changes are mostly limited formatting.

It's helpful to have a copy of the pre-conversion guide for comparison.
I've placed a chunked copy online at
http://www.wireshark.org/~gerald/wsdg_html_2014_01/ .

Tested under Autotools. Nmake and CMake will likely break. I'll take a
look shortly. If only we had documention adding a feature branch to
Gerrit and using it to test different platforms...

svn path=/trunk/; revision=54945