shared: Begin db migration logic

Issue: #26

shared/dbmigrator.h

@@ -0,0 +1,24 @@
+#ifndef DBMIGRATOR_H
+#define DBMIGRATOR_H
+#include <QStringList>
+#include <QSqlDatabase>
+#include <QObject>
+class DBMigrator : public QObject
+{
+	Q_OBJECT
+  private:
+	QSqlDatabase *db;
+
+  public:
+	DBMigrator(QSqlDatabase &db);
+	~DBMigrator();
+	uint32_t currentRevision();
+	void performMigrations();
+	QStringList getMigrationFilenames();
+	bool migrationNeeded();
+  signals:
+	void migrationDone(uint32_t);
+	void done();
+};
+
+#endif // DBMIGRATOR_H