nodes: revised text node

Clarifies text node's ability to parse HTML with Qt.
Removes janky incomplete "rich text editing" functionality. I don't think this is the right approach.

app/dialog/text/text.h

@@ -0,0 +1,51 @@
+/***
+
+  Olive - Non-Linear Video Editor
+  Copyright (C) 2021 Olive Team
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+***/
+
+#ifndef RICHTEXTDIALOG_H
+#define RICHTEXTDIALOG_H
+
+#include <QDialog>
+#include <QFontComboBox>
+#include <QPlainTextEdit>
+
+#include "common/define.h"
+#include "widget/slider/floatslider.h"
+
+namespace olive {
+
+class TextDialog : public QDialog
+{
+  Q_OBJECT
+public:
+  TextDialog(const QString &start, QWidget* parent = nullptr);
+
+  QString text() const
+  {
+    return text_edit_->toPlainText();
+  }
+
+private:
+  QPlainTextEdit* text_edit_;
+
+};
+
+}
+
+#endif // RICHTEXTDIALOG_H