Merges branch 'release/1.3.0' into develop
Removes Scanner and related code
Makes the localization variable configurable
Adds localizerVariable to Manifest.

* If present the localizerVariable will be used as the slug that the
  options are written to.
Makes OptionsManifest use the plugin slug as the localizerVariable.

* The localizing javascript variable will now be written as the
  underscorized version of the plugin slug.
Updates changelog.
Makes the javascript variable that the plugin writes configurable.

* The options variable now will correspond to the underscorized plugin
  slug name.
Adds `getLocalizedStrings` to PluginMeta.

* These strings will be passed to the plugin in the options.
* The strings will be present at the base of the javascript object
  * This ensures compatibility with the default WordPress html entity conversion.
Adds support for localized strings.

* The Localized strings are now passed to javascript.
* The options of the plugin are written in a nested, options object.
  * This has the added side-effect of being ignored by WordPress's html
    entity serialization.
  * ie:- An option's type information is no longer lost, a boolean from
    PHP is a boolean on the javascript object. No deserialization/parsing needed.
Updates changelog
Merges branch 'feature/add-localization-to-plugin-meta' into develop
Fixes localizer variable direct lookup
Fixes localizer variable assignment.
Bumps version to 1.4.0
Updates changelog for 1.4.0.
Makes the variable that the plugin writes configurable.

* The options variable now will correspond to the underscorized plugin
  slug name.
* Adds support for localized strings.
  * The options object is now nested inside the main plugin variable.
  * Type information is now preserved from PHP to Javascript.