common: function generating macros enhancements
common: function generating macros enhancements

* accessor for text
* accessor with custom member getting expression
* documentation fix
* better parameter naming

redhatrises/openscap,ybznek/openscap,OpenSCAP/openscap,isimluk/openscap,jan-cerny/openscap,isimluk/openscap,jan-cerny/openscap,ybznek/openscap,redhatrises/openscap,postfix/openscap,Hexadorsimal/openscap,Hexadorsimal/openscap,openprivacy/openscap,mpreisler/openscap,postfix/openscap,ybznek/openscap,mpreisler/openscap,openprivacy/openscap,openprivacy/openscap,ybznek/openscap,OpenSCAP/openscap,OpenSCAP/openscap,postfix/openscap,ybznek/openscap,Hexadorsimal/openscap,Hexadorsimal/openscap,Hexadorsimal/openscap,redhatrises/openscap,jan-cerny/openscap,postfix/openscap,mpreisler/openscap,isimluk/openscap,OpenSCAP/openscap,OpenSCAP/openscap,jan-cerny/openscap,openprivacy/openscap,isimluk/openscap,mpreisler/openscap,postfix/openscap,redhatrises/openscap,Hexadorsimal/openscap,postfix/openscap,isimluk/openscap,isimluk/openscap,mpreisler/openscap,OpenSCAP/openscap,jan-cerny/openscap,mpreisler/openscap,openprivacy/openscap,ybznek/openscap,redhatrises/openscap,openprivacy/openscap,jan-cerny/openscap,redhatrises/openscap