Allow for inline editing of dynamic content macros

This request is for Confluence to allow apps to provide dynamic content macro editing inline with the Confluence editor.

Dynamic content macros can contribute custom editors by specifying an editor field with appropriate sub-fields such as "url" to identify the resource providing the editor. When editing a page containing a dynamic content macro with a custom editor, a web panel displays the dynamic content macro in "view mode" instead of "edit mode". The user must click the pencil icon to open a dialog to see the dynamic content macro in edit mode.

An `{output.type}` context parameter can be specified in the macro's view resource URL so conceivably the app could provide an edit version of the macro if it detects the output type is `preview`, however, Confluence places a mask over the macro to prevent interaction. 

An aggressive solution would involve always displaying the macro's editor in the Confluence editor, but a more conservative approach would allow apps to opt-in to inline editing by supplying a new field within the custom `editor` section. For example:

{
  "url": "/my-view-resource",
  ...
  "editor": {
    "url": "/my-editor-resource",
    "inlineEditing": true,
    ...
  }
}