1.0.2: More functions

This pretty much completes the coverage of built-in DS functions,

• Added qs_*_read and qs_*_write functions.
• Added qs_map_secure_* functions.
• Added qs_type_* macros mapping to ds_type_*
  [this allows you to pretty much just find-replace "\bds_" to "qs_" in GMEdit with Regexp option]
• Added qs_get_index(value) for converting to non-qs indexes
  (if you need to pass a QS to an unrelated built-in function that takes ds).
• Added qs_debug_mode constant.
  (for determining whether you are using qs_one or qs_zero version)
• Added qs_debug_dump(value) for formatted printing.