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)
Merge pull request #33 from oncletom/feature-data-src-dynamic

[READY] availableWidths as a function