window size states not saved properly

I think I have found two minor errors in gqview when
saving window position.

Right now when gqview exits, it saves the position and
size if the window isn't maximized.

It needs to always save the position and size of where
gqview would be if it were not maximized even if it is.

I tried to modify the source code to do this, and I
could not figure it out. I'm not sure if it's possible
to do this.

My attached patch fixes the first problem

To recreate these errors, first make sure window
position saving is on in preferences

This error is a bigger problem but only happens with
more than one monitor:
1. run gqview
2. make it unmaximized
3. move it to a different monitor than it was on
4. maximize it
5. quit
6. run gqview

error: gqview will be on the wrong monitor

second error:
1. run gqview
2. make it unmaximized
3. move the window somewhere else
4. maximize it
5. quit
6. run gqview
7. unmaximize it

error: it won't be were it was moved to, but instead
the previous position. When my patch is applied, it
won't be at the previous position either, but a default
position.

I have read in documentation that it is best to let the
window manager handle saving window sizes and positions
rather than trying to use functions to do it. I am
inexperienced at gtk and am not sure how to do this.