Platform detection added for wine, Windows 7, and 8. Refs: #33.
The changes are as proposed in CPC 1.7 rc5 plus:
- a bug fix in HostDialog.IsWine where the flag isWine must be set in case of TRUE
- changes added to System/Docu/Dialog.

Signed-off-by: Josef Templ <josef.templ@gmail.com>