Event tests
Splitting events registration to hook tests on them

- moved event setup to init
- created dedicated method to register events whenever you want
Fixing boolean init

Enabling Chrome for debug as the stack trace is more readable.
Using `opts.hasOwnProperty` instead of `'property' in opts`
Merge pull request #25 from oncletom/feature-optional-events

[READY] Triggering on Events/Manually
add support for umd
Test framework and jshint adjustments
Testing dynamic size computation
Implementing dynamic size calculation
Making the stub comment more explicit about its meaning.
A 1030 witdh should select 1024 instead of 320.
So electing the biggest available width first.
Jshint compliance

- dealing with global/external variables
- removing `Imager` variable declaration (as now used as a function)