DWDS/Dialing Concordance Code

+ tagged ddc-2.2.4

* ddc v2.2.4 release cleanup

+ tagged ddc-2.2.4-rc1

+ tagging v2.2.4-rc1

+ query-lexer fine-tuning for negative dates (interference from fixes for mantis #19051 "6-er")

* added linux kernel-style branch prediction macros likely(), unlikely()
* added index-compile-time negative-year support for CBibliography::ConvertDateToInt()
* hacked slice computation for negative years in CQCountKeyExprDateSlice::Evaluate()
+ slice labels always round *down*, even for negative slices, e.g. slice(1974/10)=1970 but slice(-1974/10)=-1980
+ without this hack, slice-label 0 would cover a 20-year interval (-10..9)

+ updated scripts/{int2date,date2int}.perl for signed-year encoding

+ added support for negative years in utilit.cpp date2int(), int2date()
- probably breaks date-savvy indexing & runtime code

+ optimized out implicit regex for negative literal filter conditions in in CFreeBiblStringIndex::GetFilterValue()

* updated version (work in progress)