Provide an error message if python isn't installed.

Closes #14.
Added Navigation Timing via Resource Timing where available, plus actual requested URL and cached info
replaced resource timing metrics array by regular object traversal checking for 'Start' or 'End'
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
normalized relative resource timing into absolute navigation timing for all requestes but load type which uses relative resource timing
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.
Use the history object in an iframe to prevent cases where history.pushState and History.prototype.pushState are overwritten.
Merge pull request #26 from awbraunstein/history-iframe

Use the history object in an iframe
Create NPM package.json file.

Progress on #6 and #7.
Added absolute Navigation Timing via normalized relative Resource Timing where available, plus actual requested URL and cached info to response.timing object.
conflict
Remove the latest history state on redirects to fix behavioral differences between Chrome and FF.