Update the pipeline to latest software version.

* We now require seesaw 0.0.15
* We accept the latest git-lua (AKA 1.14.lua.20130523-9a5c)
* We remplace the binary and the get-wget-lua.sh with the updated version from posterous-grab
Merge pull request #2 from nsapa/to_AT

Update the pipeline to latest software version.