3.5.2

One contribution from @shdwcat:

• The member variable __snap_field_order is created in structs built using snap_from_yaml() if the [trackFieldOrder] argument is set to true

Addresses the following issues:
#5 - Methods and functions are now duplicated by snap_deep_copy(). Please note that complex references between structs may cause method duplication to behave strangely
#8 - UTF8 byte order mark is now ignored when loading a string from a file