Improve the way how Xporter handles scopes and add new scopes.

Xporter must provide the following scopes:

• Agile Boards - This new scope is related to Agile Backlog, Active Sprint, and Kanban board.
• Agile Releases - This new scope is related to Agile Releases. This scope refers to list and detail page.
• JSD Queues - This new scope is related to Jira Service Desk Agent Queues view.

Only templates with the respective scope must be shown depending on the screen.