Fix styling of database tag view in main window

* Also allow collapsing the entire left splitter instead of a dedicated option to hide the group view.

src/core/Config.cpp

@@ -93,7 +93,6 @@ static const QHash<Config::ConfigKey, ConfigDirective> configStrings = {
     {Config::GUI_Language, {QS("GUI/Language"), Roaming, QS("system")}},
     {Config::GUI_HideToolbar, {QS("GUI/HideToolbar"), Roaming, false}},
     {Config::GUI_MovableToolbar, {QS("GUI/MovableToolbar"), Roaming, false}},
-    {Config::GUI_HideGroupsPanel, {QS("GUI/HideGroupsPanel"), Roaming, false}},
     {Config::GUI_HidePreviewPanel, {QS("GUI/HidePreviewPanel"), Roaming, false}},
     {Config::GUI_AlwaysOnTop, {QS("GUI/GUI_AlwaysOnTop"), Local, false}},
     {Config::GUI_ToolButtonStyle, {QS("GUI/ToolButtonStyle"), Roaming, Qt::ToolButtonIconOnly}},
@@ -365,6 +364,7 @@ static const QHash<QString, Config::ConfigKey> deprecationMap = {
     {QS("GUI/DarkTrayIcon"), Config::Deleted},
 
     // 2.7.0
+    {QS("GUI/HideGroupsPanel"), Config::Deleted},
     {QS("LastAttachmentDir"), Config::Deleted},
     {QS("KeeShare/LastDir"), Config::Deleted},
     {QS("KeeShare/LastKeyDir"), Config::Deleted},

src/core/Config.h

@@ -74,7 +74,6 @@ public:
         GUI_Language,
         GUI_HideToolbar,
         GUI_MovableToolbar,
-        GUI_HideGroupsPanel,
         GUI_HidePreviewPanel,
         GUI_AlwaysOnTop,
         GUI_ToolButtonStyle,