Support bulk operations on reports

Problem/Motivation

Configuration Revert currently supports reverting a single configuration entity.

There may be use cases for bulk reversion. Examples:

• After experimentation, restore a module's configuration to its default state.
• Restore a Features-type module's configuration to its default state to stay on configuration upgrade path.
• When browsing a list of overridden configuration, select specific items to revert all at once.

Mass reversion might include:

• Revert all of a list of configuration entities/items.
• Revert all configuration entities of a given type.
• Revert all configuration entities provided by a given extension.
• Revert all configuration entities of a given type provided by a given extension.

Proposed resolution

Such methods could be added to a service providing reversion methods (see #2408909: Pull configuration item reversion into a separate class/service).

Possible UI changes:

• Add checkboxes to current reports to select multiple items to revert.
• Add buttons or similar elements to reports to trigger mass operations, like:
  • Add all missing configuration items
  • Revert all changed configuration items

Additional bulk operations: Export multiple -- see #3038494: Add bulk export ability

Remaining tasks

User interface changes

API changes