Update Bower to 1.2.6

Bower 1.2.6 puts its components in `./bower_components`, so this commit
also updates the paths in `Makefile` and `spec/suite.html` and changes
the ignored folder.
Don't ignore .jhw-cache

This project uses PhantomJS, not Jasmine-Headless-Webkit. There's no
reason to ignore that directory.
Improve Make / Travis experience

 * Travis uses npm 0.10.x
 * Add "install_dependencies" task, which Travis will use to install
   both NPM and Bower dependencies
 * Don't echo most shell commands from Make
 * echo "JSHint OK" if the JSHint check passes