2.0.0.0-dev80

* Framework improvements:
  * Reworked subsystem of static view files preprocessing
     * Refactored implementation of the view files "fallback" and "collecting" (layout XML files, LESS files for @magento_import) mechanisms for better abstraction
     * Used the concept of "view asset" in client code of the View library across the board
     * Refactored and simplified LESS preprocessing library, mechanisms of merging and minifying static view files
     * Reworked the way how links to static view files are generated and served):
         * Changed the strategy of generating unique URL for view static files
         * Separated the view files publication process from the page generation
         * Added a separate entry point (pub/static.php) for file materialization
     * View files deployment tool changes:
         * Renamed CLI script from generator.php to deploy.php
         * Fixed the known limitation of view files deployment tool of being unable to materialize files per languages. Now the list of intended languages can be provided as a CLI parameter
         * Expanded the tool parameters
     * Improved security and reliability of view files structure:
         * Restructured the module view folder by file type: "web"  view static files, "templates"  module template files, and "layout"  module layout files
         * Reworked the theme module folder to repeat the same structure as in the module
         * Added web folder to a theme root which contains static view files
         * Renamed the pub/lib to lib/web. Currently there are no static files that are publicly accessible by default. All static view files may be subject of preprocessing
         * Renamed the former lib to lib/internal
  * Support of RequireJS:
     * Adopted RequireJS library and implemented ability for modules or themes to introduce RequireJS configuration (aka shim-config)
     * Refactored scripts in the Magento_ConfigurableProduct module to be loaded via RequireJS
* Tax calculation updates:
  * Fixed tax calculation rounding issues when discount is applied
  * Fixed extra penny problem when exact tax amount ends with 0.5 cent
  * Fixed tax calculation errors when customer tax rate is different from store tax rate
  * Added support to round tax at individual tax rate
  * Fixed price inconsistencies between catalog and shopping cart
  * Added support to maintain consistent price including tax for customers with different tax rates
  * Added support to allow tax rules with different priorities to be applied to subtotal only
* Fixed bugs:
  * Fixed an issue where it was impossible to place an order with Zero Subtotal Checkout using checkout with multiple addresses
  * Fixed an issue where an irrelevant  confirmation window appeared when placing an order with Zero Subtotal Checkout in the backend
  * Fixed an issue where it was impossible to create an order for a new customer in the backend if gift options were  enabled
  * Fixed an issue where a wrong message about backordered items in cart was displayed in the backend
  * Fixed an issue where it was impossible to perform a checkout with multiple addresses when the  Validate Each Address Separately option in Multi-address Checkout was enabled
  * Fixed an issue where the Minimum Order Amount option was applied to the orders
  * Fixed an issue where the duplicated element  caused  problems when attempting to customize styling  of the section
  * Fixed an issue where a user was redirected to Dashboard when clicking the Search  and Reset buttons on the Recurring Profile page
  * Fixed an issue where the Enabled for RMA option was available for online shipping method in Magento 2 CE
  * Fixed an issue when free shipping was applied even if the Free Shipping with Minimum Order Amount option was disabled
  * Fixed an issue with not displaying a downloadable product with the Links can be purchased separately option enabled on the grouped product page
  * Fixed an issue of not generating product price variations during configurable product creation
  * Fixed an issue with incorrect work of category pager
  * Fixed an issue with file permissions change after the system backup was run
  * Fixed an issue with inconsistency between the REST request and response format
  * Fixed an issue with the Magento Contact Us form not submitted if secure_base_url doesn't contain "https"
  * Fixed an issue with incorrect display of the Price as configured field which didnt count product options cost
  * Fixed an issue with incorrect redirect when clicking the product URL in Pending Review Rss
* JavaScript improvements:
  * Added standard validation to the front-end address fields
  * Implemented the wishlist widget
  * Implemented the tabs widget
  * Implemented the collapsible widget
  * Implemented the accordion widget
  * Implemented the tooltip widget
  * Standardized widgets used on one page checkout