* [SC] Many adaptations throughout, due to DCG cleanups.
* [ABNF2DCG,SC] Dependency on ABNF standard, not custom DCG rule.
* [DCG_ASCII,DOC] Documented all predicates in export list.
* [DCG_ASCII,NEW] Added //2 variant of all bracket DCGs, adding the type (curly, square, round).
* [DCG_CONTENT,NEW] Added bracketed//[1,2] and quoted//1.
* [DCG_GENERIC,DCG_COLLECTION,DCG_CONTENT,DCG_CONTROL,DCG_DEBUG,DCG_ERROR,DCG_META,DCG_PEEK,DCG_STREAM,DCG_REPLACE,PARSE_TREE,SC] Big reorganization of DCG modules.