Create outline region based on comments

[antony-booth-leclanche]

Some nodes may be large and contain lots of items and it would be helpful to create collapsible regions around some child nodes using comments, similar to Visual Studio '#Region' directive, where 2 consecutive comments beginning with 'region"' creates a collapsible region, or something like 'start-region', 'end-region' to denote the opening and closing comment of a collapsible block. E.G:-

Resources
v  #start-region: Starts a collapsible region for Permissions
|  Permission
|    Something
|    SomethingElse
|
|  Permission2
|    Something
|    SomethingElse
|  #end-region: Marks the point where the region collapses for all Permissions resources

v  #start-region: Tables (note: the colon after 'start-region' is just part of the comment, not a tag identifier)
|  Table
|    Something
|    SomethingElse
|
|  Table2
|    Something
|    SomethingElse
|  #end-region: Tables