windows.c: Added support for "int" configuration storage

This patch addes body to the functions subsurface_get_conf_int()
and subsurface_set_conf_int().

It also makes some small changes:
- subsurface_get_conf_bool() now uses subsurface_get_conf_int()
- for retrieving DWORDS we would only need RegQueryValueEx,
thus the wchar_t conversations aren't really needed, unless
we start storing integers in keys with UTF-8 characters in the name.

Signed-off-by: Lubomir I. Ivanov <neolit123@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Request a minimal height for the notes in the dive edit dialog

This sould give the notes text box around 8 lines of text.

Signed-off-by: Lubomir I. Ivanov <neolit123@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>