Method: Render the settings page for this plugin.
Method: Highlight the proper top level menu.
Method: Get free unused menu position. This function helps prevent other plugin menu conflict when assigned to same position.
Action Hook: Action hook for adding custom menu in wp-admin.
Method: Register the administration menu for this plugin into the WordPress Dashboard menu.
Method: Menu counter
Method: Register and enqueue admin-specific JavaScript.
Method: Register and enqueue admin-specific style sheet.
Method: Include files required in wp-admin
Method: Initialize the plugin by loading admin scripts & styles and adding a settings page and menu.