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'
normalized relative resource timing into absolute navigation timing for all requestes but load type which uses relative resource timing
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
Merge pull request #19 from marcelduran/add_navigation_resource_timing

Add Navigation Timing via Resource Timing where available