Update debian and ubuntu for CVE-2014-6273
Merge pull request #207 from tianon/CVE-2014-6273

Update debian and ubuntu for CVE-2014-6273
initial testing on using bash to build repos
Replace "LIBDIR" with "LIBRARY" and make it user-specifiable
Add "SRC" and actually clone repos
Add a little "cloning" output so it's clear why the script hangs
Add actual building and some handy logging
add usage, only build all with `--all` argument
warn users about unknown 'repo:tag' combinations
script for pushing library images
Add "git-set-dir-times" and "git-set-file-times" (whoops)
Update "git-set-dir-times" to use "--no-dereference" so my fun mkimage.sh symlink in my Debian repo doesn't break on not-my-machine :D
getopt added for much beauty
Parameterize library, src, logs, and namespaces
Use magic extglob bash syntax instead of explicitly ignoring MAINTAINERS in our loop
Update "git fetch" with intelligence about when to go fetch (ie, if we don't have the ref specified)
Add magic support for direct operation on files

Things that work now: (in any combinations)
- `./build.sh debian`
- `./build.sh debian:sid`
- `./build.sh ../library/debian`
- `./build.sh ../library/debian:sid`
Tweak build/clone logic to always do a checkout, and to bail gracefully when a commit doesn't exist (skipping the relevant repoTag build)
Disable "gc.auto" for all our cloned repos to help ensure dangling commits don't get reclaimed (since we might need them later)
migrate the extra options from build.sh