CRM-14479 - Implement "/civicrm/a" page

This page is a container for Angular-based pages. To develop a new Angular-based page,
one would:

a) Create a JS file which defines an Angular module. (The file should start
out with "var myModule = angular.module(...)".)

b) Register the module-name/file-name. This can be registered either by:

 - If writing a CiviCRM extension, then implement hook_civicrm_angularModules.
 - If writing a CiviCRM component, then implement getAngularModules().
CRM-14479 - Implement example extension with an Angular module
Update README.md
CRM_Core_Resources - Fix PhpStorm warnings
CRM-14479 - hook_angularModules - Allow specifying multiple *.js files for one module
CRM-14481 - crmCaseType - First pass at Angular-based case-type screen (view-only)
CRM-14481 - crmCaseType - Use tabs and accordions from jQuery UI
CRM-14481, CRM-14479 - Load CSS for Angular modules
CRM-14480 - Allow creation/deletion of activity sets
CRM-14479 - Load minified angular.js by default

Note: CRM_Core_Resources changes ".min.js" to ".js" if debugging is enabled.
CRM-14480 - crmCaseType - Prettier URL construction
CRM-14481 - crmCaseType - Styling for accordion, trash icon
CRM-14481 - crmCaseType - Styling for trash icon
CRM-14483 - Only allow addition of "Sequence" if we don't have a sequence already
CRM-14480 - crmCaseType - Make cells editable (per mockup)
CRM-14483 - crmCaseType - Implement row addition for "Activity Types" table
CRM-14483 - crmCaseType - Implement row addition for activity sets

This abstracts some of the code used for addition of activity types
CRM-14484 - crmCaseType - Make activity lists sortable
Merge pull request #3210 from totten/master-casetype-rebased

CRM-14479, CRM-14480 - Add Angular and basic Case Type UI.