missing uglify-js, make browser fails on sed

## Expected
1. uglify-js should be a dev-dependency in npm `package.json`
2. `make browser` builds correctly
## Actual

Output as follows...

```
# super hacky build script for browser version!
# etc...
echo "nodeunit.run = reporter.run;" >> dist/browser/nodeunit.js
echo "return nodeunit; })();" >> dist/browser/nodeunit.js
sed -i "/\@REMOVE_LINE_FOR_BROWSER/d" dist/browser/nodeunit.js
sed: 1: "dist/browser/nodeunit.js": extra characters at the end of d command
make: *** [browser] Error 1
```

Read npm package.json and the make browser target, then run make browser to reproduce the sed failure. Done means uglify-js is declared as a dev dependency and the browser build completes without the reported error.

Written by the indexing model from the issue text.