Properly save and restore geometry of windows

Use event filter in configuration manager to save and restore
geometry of windows.

Save geometry on QEvent::WindowDeactivate and restore it on
QEvent::WindowActivate.
Merge pull request #208 from sschuberth/master

Add a large wizard image to the first installer page
Initialize window geometry when created
Updated translations; added Simplified Chinese
Install translation into separate directory
Remove signal/slot connections for removed slots
Windows: Refactor Inno Setup config file

Inno Setup takes files from build and Qt directories

Custom configuration can be changed in file pointed by
COPYQ_INNO_SETUP environment variable.
Translated using Weblate (Simplified Chinese)

Currently translated at 11.1% (69 of 618 strings)
Merge remote-tracking branch 'origin/master'
Fix translations selection

Load compiled translations in "src/" in debug mode.

Resize combo box with translations to fit the largest language name.

Set correct current item in language combo box from current locale.
Added Weblate link and diacritics to about dialog
Print warning if option has invalid value in config file
Translated using Weblate (Czech)

Currently translated at 95.3% (640 of 671 strings)
Translated using Weblate (Simplified Chinese)

Currently translated at 16.6% (103 of 618 strings)
Merge remote-tracking branch 'origin/master'
Drag'n'drop items to tabs
Translated using Weblate (Ukrainian)

Currently translated at 0.8% (5 of 618 strings)
Merge remote-tracking branch 'origin/master'
Translated using Weblate (Ukrainian)

Currently translated at 0.8% (5 of 618 strings)
Translated using Weblate (Ukrainian)

Currently translated at 2.2% (14 of 618 strings)