Fix Settings UI inconsistencies (#1202)

* Move "About" tab in Settings

* Resize Settings window

This prevents from spawning horizontal scroll (which is caused by too long line
in "Attributions" group)

* Fix "show license" link width

If you clicked empty space next to link application assumed you clicked link.
I fixed that by using QLabels instead of SignalLabel (there's something "wrong"
with them, but I couldn't find what)

src/widgets/dialogs/SettingsDialog.cpp

@@ -38,7 +38,7 @@ SettingsDialog::SettingsDialog()
     this->overrideBackgroundColor_ = QColor("#111111");
     this->themeChangedEvent();
 
-    this->resize(766, 600);
+    this->resize(815, 600);
 }
 
 void SettingsDialog::initUi()
@@ -54,7 +54,7 @@ void SettingsDialog::initUi()
         .withoutMargin()
         .assign(&this->ui_.tabContainer);
 
-    this->ui_.tabContainerContainer->layout()->setContentsMargins(8, 8, 0, 8);
+    this->ui_.tabContainerContainer->layout()->setContentsMargins(8, 8, 0, 39);
 
     this->layout()->setSpacing(0);
 
@@ -129,6 +129,7 @@ void SettingsDialog::addTabs()
 
     this->ui_.tabContainer->addStretch(1);
     this->addTab(new AboutPage, Qt::AlignBottom);
+    this->ui_.tabContainer->addSpacing(16);
 }
 
 void SettingsDialog::addTab(SettingsPage *page, Qt::Alignment alignment)