Feature/01 library browser

[vanrez-nez]

closes #1

@daltonrooney this is the first version of the browser featuring:

• Component Explorer (Sidebar)
• Component Preview inside an iframe and toolbar with Open in new tab and Fullscreen buttons
• Component Toolbar tabs showing View code and contexts source code plus some basic info.

There are pending features I think would be nice to have, but I think is better to open specific enhancements as new issues to be able to focus on other tasks.

[daltonrooney]

Thanks @vanrez-nez! I will run a test before our call today.