Remember rename settings and window state

[Jens-Olaf-Mueller]

Depends on #90.

This adds optional persistence for Bulky's rename settings and always preserves the window state.

Changes:

• add a "Remember last settings" checkbox
• persist the checkbox state
• save and restore rename options when enabled
• save and restore the last file chooser location when enabled
• preserve window width and height
• preserve maximized state
• do not persist minimized state
• unify Close, Quit and window-close handling so settings are saved before widgets are destroyed
• keep existing UI defaults when "Remember last settings" is disabled
• update GSettings schema and translation template

Tested successfully with:

• remember settings enabled and disabled
• all rename operation settings restored
• last chooser location restored
• normal window size restored
• maximized state restored
• minimized state not persisted
• Close button, Quit menu and window close button