Undocumented predicates

The following predicates are exported, but not or incorrectly documented.

 dcg_peek(Arg1, Arg2, Arg3)

 do_dcg_util_tests

 isVar(Arg1)

 isQVar(Arg1)

 isVarOrVAR(Arg1)

 file_eof(Arg1, Arg2)

 charvar(Arg1)

 cspace(Arg1, Arg2)

 cwhite(Arg1, Arg2)

 mw(Arg1, Arg2, Arg3)

 bx(Arg1)

 zalwayz(Arg1, Arg2, Arg3)

 zalwayz(Arg1)

 one_blank(Arg1, Arg2)

 set_dcg_meta_reader_options(Arg1, Arg2)

 phrase_from_stream_nd(Arg1, Arg2)

 parse_meta_term(Arg1, Arg2, Arg3)

 read_string_until(Arg1, Arg2, Arg3, Arg4)

 read_string_until_no_esc(Arg1, Arg2, Arg3, Arg4)

 dcgOneOrMore(Arg1, Arg2, Arg3)

 dcgOptional(Arg1, Arg2, Arg3)

 dcgZeroOrMore(Arg1, Arg2, Arg3)

 dcgOptionalGreedy(Arg1, Arg2, Arg3)

 dcgAnd(Arg1, Arg2, Arg3, Arg4)

 dcgAnd(Arg1, Arg2, Arg3, Arg4, Arg5)

 dcgAnd(Arg1, Arg2, Arg3, Arg4, Arg5, Arg6)

 dcgMust(Arg1, Arg2, Arg3)

 dcgSeqLen(Arg1, Arg2, Arg3)

 dcgOr(Arg1, Arg2, Arg3, Arg4)

 dcgNot(Arg1, Arg2, Arg3)

 theString(Arg1, Arg2, Arg3)

 theString(Arg1, Arg2, Arg3, Arg4)

 theText(Arg1, Arg2, Arg3)

 theCode(Arg1, Arg2, Arg3)

 dcgLenBetween(Arg1, Arg2, Arg3, Arg4)

 notrace_catch_fail(Arg1)

 notrace_catch_fail(Arg1, Arg2, Arg3)

 do_dcgTest(Arg1, Arg2, Arg3)

 do_dcgTest_startsWith(Arg1, Arg2, Arg3)

 decl_dcgTest_startsWith(Arg1, Arg2)

 decl_dcgTest_startsWith(Arg1, Arg2, Arg3)

 decl_dcgTest(Arg1, Arg2)

 decl_dcgTest(Arg1, Arg2, Arg3)

 dcgReorder(Arg1, Arg2, Arg3, Arg4)