#42

 - symbolic constants for Delphi versions (internal, numeric versions)

 - DelphiVersion() method to map "delphi" options flag to DELPHI_XXX version

 - DelphiVersionName() method to provide human meaningful name of DELPHI_XXX version number

 - build() method modified to use DelphiVersion() and DelphiVersionName() to support non-numeric delphi version in options object (e.g. "XE", "XE2" etc)