Miscellaneous small fixes (#1972)

* m_captureWindow->activateWindow(), raise()

Signed-off-by: Haris Gušić <harisgusic.dev@gmail.com>

* Revert "m_captureWindow->activateWindow(), raise()"

This reverts commit 36320aa38a9584864a5fab32a2ce4872ff5ad072.

* screen --number: indicate 0-indexation

Signed-off-by: Haris Gušić <harisgusic.dev@gmail.com>

* Fix color update bug

Also refactored SidePanelWidget sigslots related to color change.

Signed-off-by: Haris Gušić <harisgusic.dev@gmail.com>

* Stop creating empty flameshot.conf file

Signed-off-by: Haris Gušić <harisgusic.dev@gmail.com>

src/main.cpp

@@ -186,7 +186,7 @@ int main(int argc, char* argv[])
                   "nothing if raw is specified"));
     CommandOption screenNumberOption(
       { "n", "number" },
-      QObject::tr("Define the screen to capture") + ",\n" +
+      QObject::tr("Define the screen to capture (starting from 0)") + ",\n" +
         QObject::tr("default: screen containing the cursor"),
       QObject::tr("Screen number"),
       QStringLiteral("-1"));