Fix spacing of QGroupBox's

* Previously our base style sheet added roughly 20px of margin to the top and bottom of all QGroupBox. This caused visual errors where that margin was not needed/desired. 
* Transferred padding to the specific layouts instead where it belongs.

src/gui/ApplicationSettingsWidgetGeneral.ui

@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>605</width>
-    <height>968</height>
+    <height>969</height>
    </rect>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout_3" stretch="0">
@@ -64,7 +64,7 @@
           </property>
           <layout class="QVBoxLayout" name="verticalLayout_8">
            <property name="spacing">
-            <number>0</number>
+            <number>20</number>
            </property>
            <property name="leftMargin">
             <number>0</number>
@@ -944,22 +944,6 @@
              </layout>
             </widget>
            </item>
-           <item>
-            <spacer name="verticalSpacer_2">
-             <property name="orientation">
-              <enum>Qt::Vertical</enum>
-             </property>
-             <property name="sizeType">
-              <enum>QSizePolicy::Fixed</enum>
-             </property>
-             <property name="sizeHint" stdset="0">
-              <size>
-               <width>20</width>
-               <height>10</height>
-              </size>
-             </property>
-            </spacer>
-           </item>
            <item>
             <layout class="QHBoxLayout" name="resetSettingsSubLayout">
              <property name="spacing">

src/gui/ApplicationSettingsWidgetSecurity.ui

@@ -11,6 +11,9 @@
    </rect>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout">
+   <property name="spacing">
+    <number>20</number>
+   </property>
    <property name="leftMargin">
     <number>0</number>
    </property>

src/gui/PasswordGeneratorWidget.ui

@@ -208,6 +208,9 @@ QProgressBar::chunk {
        <string>Password</string>
       </attribute>
       <layout class="QGridLayout" name="_2">
+       <property name="verticalSpacing">
+        <number>10</number>
+       </property>
        <item row="0" column="0">
         <layout class="QHBoxLayout" name="passwordLengthSliderLayout">
          <property name="spacing">

src/gui/dbsettings/DatabaseSettingsWidgetBrowser.ui

@@ -23,6 +23,9 @@
    </size>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout">
+   <property name="spacing">
+    <number>20</number>
+   </property>
    <property name="leftMargin">
     <number>0</number>
    </property>
@@ -88,6 +91,9 @@
           <verstretch>0</verstretch>
          </sizepolicy>
         </property>
+        <property name="toolTip">
+         <string>Convert legacy KeePassHTTP attributes to KeePassXC-Browser compatible custom data</string>
+        </property>
         <property name="text">
          <string>Disconnect all browsers</string>
         </property>

src/gui/dbsettings/DatabaseSettingsWidgetDatabaseKey.cpp

@@ -48,6 +48,7 @@ DatabaseSettingsWidgetDatabaseKey::DatabaseSettingsWidgetDatabaseKey(QWidget* pa
 {
     auto* vbox = new QVBoxLayout(this);
     vbox->setSizeConstraint(QLayout::SetMinimumSize);
+    vbox->setSpacing(20);
 
     // primary password option
     vbox->addWidget(m_passwordEditWidget);
@@ -59,6 +60,7 @@ DatabaseSettingsWidgetDatabaseKey::DatabaseSettingsWidgetDatabaseKey(QWidget* pa
     vbox->setSizeConstraint(QLayout::SetMinimumSize);
     m_additionalKeyOptions->setLayout(new QVBoxLayout());
     m_additionalKeyOptions->layout()->setMargin(0);
+    m_additionalKeyOptions->layout()->setSpacing(20);
     m_additionalKeyOptions->layout()->addWidget(m_keyFileEditWidget);
 #ifdef WITH_XC_YUBIKEY
     m_additionalKeyOptions->layout()->addWidget(m_yubiKeyEditWidget);

src/gui/dbsettings/DatabaseSettingsWidgetGeneral.ui

@@ -23,6 +23,9 @@
    </size>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout">
+   <property name="spacing">
+    <number>20</number>
+   </property>
    <property name="leftMargin">
     <number>0</number>
    </property>

src/gui/dbsettings/DatabaseSettingsWidgetMaintenance.ui

@@ -23,6 +23,9 @@
    </size>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout">
+   <property name="spacing">
+    <number>20</number>
+   </property>
    <property name="leftMargin">
     <number>0</number>
    </property>

src/gui/styles/base/basestyle.qss

@@ -48,13 +48,11 @@ DatabaseOpenWidget #centralStack {
 }
 
 QGroupBox {
-    margin-top: 1.4em;
-    margin-bottom: 1.4em;
     font-weight: bold;
 }
 
 QGroupBox::title {
-    margin-top: -3.35em;
+    margin-top: -.4em;
     margin-left: -.4em;
     subcontrol-origin: padding;
 }