- Added `-q` to the zip command to create the archive since Travis
was having trouble handling its very long output (thus making
the build fail).
- Moved the actual building of the index and the archive from
deploy.sh to a new build.sh script.
- Added a `script` step in .travis.yml to run build.sh after npm
test.
- Specified a clone depth of 1 in .travis.yml to make things faster
since we don't need to do any git operation during the build.