Valgrind: Add gui option "Detect self-modifying code"

Setting this option to e.g. "Everywhere Except in File-backend Mappings"
allows to 'valgrind' Qt Creator itself.

Without that option the valgrind process will die if certain code paths
are executed.

Change-Id: I8888456d324a25ce092f0b0128407adf2159f496
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>
Valgrind: Memcheck: Add gui options for --show-origins and --leak-check

Change-Id: If07c7a7a11a4c555e26b672bebb1e93eded38dc4
Reviewed-by: hjk <hjk121@nokiamail.com>