Refactor OAuth2 application management views

aleksis/core/menus.py

aleksis/core/models.py

aleksis/core/rules.py

...is/core/templates/oauth2_provider/application/create.html

...is/core/templates/oauth2_provider/application/detail.html

aleksis/core/templates/oauth2_provider/application/edit.html

aleksis/core/templates/oauth2_provider/application/list.html

...templates/oauth2_provider/application_confirm_delete.html

...is/core/templates/oauth2_provider/application_detail.html

aleksis/core/templates/oauth2_provider/authorize.html

...re/templates/oauth2_provider/authorized-token-delete.html

aleksis/core/urls.py

aleksis/core/views.py