Splitting emdebian-tools and cross building translations

Separating out keyring and rootfs support

 emdebian-archive-keyring - GnuPG archive keys for the emdebian repository

 emdebian-rootfs - emdebian root filesystem support

 emdebian-tools - emdebian crossbuilding tool set

 libemdebian-tools-perl - emdebian support library

Finally got to test a request from some months ago to create a separate archive keyring for those people who just want to use the toolchains.
I also took the chance to split out the scripts to build root filesystems from the scripts that build the packages for the repository. The Emdebian::Tools module was best split out too, it's needed for emdebian-rootfs and emdebian-tools.
Not sure when this is going to happen for real, it's only a test branch right now.
(browse SVN). It tests OK, so far and if other things check out, this could be 0.8.4 (in Emdebian), then whilst the same code badged as 0.9.0 spends time in the NEW queue so that I can upload 0.8.5 etc. to Emdebian, followed by 0.9.1 with the changes from 0.8.5 onwards.

TDeb changes from Fosdem

In the main trunk (0.8.3), I've updated a few parts of em_installtdeb but I haven't made much progress on whether TDebs should be Architecture: all or Architecture: any.

1. A big endian .mo file from powerpc works fine on little endian amd64.


2. msgfmt --alignment does not seem to do what I expected (but then I'm not entirely sure what I did expect).


3. I can't find anyone cross-building .mo files - maybe it's my Google skills but if it was essential, I find it hard to think that all those cross-built systems are doing something different to just msgfmt -o $@ $.