Indexes extension methods to improve Kotlin interop
5.3
Create an index key for an ascending index on the given fields.
Create an index key for a descending index on the given fields.
Create an index key for a 2d index on the given field.
Create an index key for an 2dsphere index on the given fields.
Create an index key for a hashed index on the given property.
Create an index key for a text index on the given property.