Changed cakefile to build hallo.js & hallo-min.js to a ./build folder, and added the build folder to .gitignore
This should make it easier to include as a library in other projects.
The old examples/hallo.js target still exists as "update_examples"
Changed cakefile to output built JS files to a ./build folder, and ad…
…ded ./build to .gitignore
changed readme to reflect new location for built files