+ first parameter offset in stack now portable
* rename some constants
+ move some cpu stuff to other units
- remove unused constents
* fix stacksize for some targets
* fix generic size problems which depend now on EXTEND_SIZE constant
in most cases and not written to the ppu
* add mangeledname_prefix() routine to generate the prefix of
manglednames depending on the current procedure, object and module
* removed static procprefix since the mangledname is now build only
on demand from tprocdef.mangledname