Added macro Standard_NODISCARD equivalent to C++17 attribute [[nodiscard]] for compilers that support this.
Using Standard_NODISCARD macro for methods that create new object in gp, math, Geom, Bnd packages.
Marked equivalent operators with Standard_NODISCARD, if they are defined close to relevant methods.
Corrected code where warnings on unused result of calls to methods creating new objects are generated.
In most cases it looks like spelling errors (e.g. Normalised() instead of Normalise())
Automatic upgrade of OCCT code by command "occt_upgrade . -nocdl":
- WOK-generated header files from inc and sources from drv are moved to src
- CDL files removed
- All packages are converted to nocdlpack
