[ENHANCEMENT] Remember size and position of the "Edit log message" window

[Santiago Gonzalez]

I have two monitors. My IDE is on my primary screen, so I usually open TortoiseSVN on my secondary screen.

The problem is that the "Edit log message" dialog always opens on the primary monitor at a fixed position, ignoring where it was last used.

It would be great if the dialog remembered its last size and position, similar to how other TortoiseSVN dialogs already behave.