Create NPM package.json file.

Progress on #6 and #7.
Merge pull request #13 from nicksay/npm

Create NPM package.json file.
Convert external project dependencies from git submodule to unmanaged downloads.

Ninja
- Downloaded and extracted by the configure.py script

web.py
- Downloaded and extracted if needed during the Ninja build

Progress on #14.
Merge pull request #15 from nicksay/deps

Convert external project dependencies from git submodule to unmanaged downloads.
Provide an error message if python isn't installed.

Closes #14.
Merge pull request #17 from nicksay/deps-python

Provide an error message if python isn't installed.
Upgrade to Closure Compiler v20140625 (requires Java 7).

Also update Makefile to output a status message when running Ninja.

Closes #16.
Merge pull request #20 from nicksay/latest-compiler

Upgrade to Closure Compiler v20140625 (requires Java 7).
Minor adjustments to Markdown and Makefile style.
Merge pull request #21 from nicksay/formatting

Minor adjustments to Markdown and Makefile style.
Update to 2.0.0-alpha.2
Merge pull request #23 from nicksay/npm

Update to 2.0.0-alpha.2
Refactor navigation event handling.

*   Introduce new events and request callbacks to more consistently provide
    parity between the two.
*   Use dedicated functions to dispatch events and callbacks to ensure the
    custom event detail objects and callback arguments are identical.
*   Add events for handling clicks and history changes, allowing them to be
    canceled to prevent navigation.
*   Deprecate the old events and callbacks and remove unused string argument
    support for specifying callbacks.
*   Update the demo app to use the new events.

Progress on #12.
Add tests for refactored navigation events handling.

*   Ensure both events and callbacks are dispatched and executed, respectively.
*   Ensure that cancellation of events and callbacks is propagated.
*   Ensure that passed data is identical for events and callbacks.
*   Ensure that canceling callbacks or skipping events does not dispatch events.

Progress on #12.
Merge pull request #22 from nicksay/events

Refactor navigation event handling.