Ignore goog files not needed for runtime on npm package #24

Your module when installed is very heavy, because inclusion of some files on closure/goog:

Here is the list of folders with size > 1MB in closure/goog:

du -h -d 1 | grep M
1,3M    ./net
4,3M    ./ui
4,8M    ./i18n
1,5M    ./testing
1,5M    ./demos
1,4M    ./labs
1,1M    ./dom
1,3M    ./editor
28M     .

Total module size is 29MB

I think its safe to remove at least demos, testing, maybe all .css and .html files in subfolders (there is a lot of them)?
What do you think?