1.15.0

Implemented a delete command and associated tests for deleting a node from YAML input. This behaves in a similar manner as the write command.

The following functionality is not provided, although could conceivably be added with a modicum of additional effort if there is strong opinion that they are required:

Specify the node(s) to delete using a script (as with the write command)
Deleting common elements from all members of an array (deletions from individual members are supported using a path like a.b[0].name, but deleting from all instances in one pass, e.g. a.b[*].name, is not).

Thanks @mhuxtable !