Implemented application login.

Minor UI improvement.
Fixed memory leaks.

core/context.h

@@ -7,10 +7,12 @@
 #include <QSqlDatabase>
 #include <QStringList>
 #include <QSettings>
+#include <QSharedPointer>
 
 #include "define.h"
 #include "core_global.h"
 #include "transaction.h"
+#include "data/core-data.h"
 
 #include <odb/database.hxx>
 #include <odb/session.hxx>
@@ -20,6 +22,7 @@ class IPlugin;
 class CORESHARED_EXPORT Context
 {
 public:
+    ~Context();
     static Context &instance();
     QList<IPlugin*> plugins();
     IPlugin *plugin(const QString &pluginId);
@@ -31,6 +34,9 @@ public:
     void destroy();
     QStringList defaultPerms();
 
+    QSharedPointer<User> currentUser() const;
+    void setCurrentUser(const QSharedPointer<User> &currentUser);
+
 private:
     Context();
     QList<IPlugin*> m_plugins;
@@ -38,6 +44,7 @@ private:
     QSettings *m_settings;
     bool m_dbOpened;
     odb::session m_session;
+    QSharedPointer<User> m_currentUser;
 
     QStringList m_solved;