Move source into a 'src' directory. Update README.md file for build

instructions.

src/SeerEditorOptionsBarWidget.cpp

@@ -0,0 +1,19 @@
+#include "SeerEditorOptionsBarWidget.h"
+
+SeerEditorOptionsBarWidget::SeerEditorOptionsBarWidget (QWidget* parent) : QWidget(parent) {
+
+    // Construct the UI.
+    setupUi(this);
+}
+
+SeerEditorOptionsBarWidget::~SeerEditorOptionsBarWidget () {
+}
+
+QToolButton* SeerEditorOptionsBarWidget::fileOpenToolButton () {
+    return fileOpenTB;
+}
+
+QToolButton* SeerEditorOptionsBarWidget::textSearchToolButton () {
+    return textSearchTB;
+}
+