Change directory structure to use src folder

[jraller]

In the interests of separating out source files that need to be part of the extension from test files that do not as a first step a "src" folder will be created. The impact to developers is that it changes how they either run web-ext or which folder they point at with Chrome as the source of the extension.

Files to move into the src folder include:

• manifest.json
• background.js
• content.js
• content_delegate.js
• install_notifier.js
• notifier.js
• options.html
• options.js
• pacer.js
• recap.js
• toolbar_button.js
• utils.js

and the folders:

• assets which contains
  • css
  • fonts
  • images
  • js

Later this will allow for the creation of a "dist" folder where the contents of the "src" folder can be manipulated automatically to potentially include things like minification, per browser targeted fixes, etc.

[mlissner]

Sounds good to me. We'll just have to think about how this might affect any other branches or open PRs that we have. I wouldn't want to break all of those (not sure if it would).

[jraller]

Implemented with https://github.com/freelawproject/recap-chrome/pull/58

[mlissner]

Oh, here's my comment I remembered making. :)