ui: Extended project setup to support creation and editing of Source Groups (issue #230)

* Turned QtProjectWizzard into window for Source Group ui
* Clicking into FilePicker when empty will open dialog right away
* Fixed environment variable use throughout all Source Group path values
* Moved Preferences to QtPreferencesWindow

bug id = 230

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src/lib_gui/qt/window/project_wizzard/QtProjectWizzardContentLanguageAndStandard.h

@@ -0,0 +1,34 @@
+#ifndef QT_PROJECT_WIZZARD_CONTENT_LANGUAGE_AND_STANDARD
+#define QT_PROJECT_WIZZARD_CONTENT_LANGUAGE_AND_STANDARD
+
+#include "qt/window/project_wizzard/QtProjectWizzardContent.h"
+
+class QComboBox;
+class QLabel;
+class SourceGroupSettings;
+
+class QtProjectWizzardContentLanguageAndStandard
+	: public QtProjectWizzardContent
+{
+	Q_OBJECT
+
+public:
+	QtProjectWizzardContentLanguageAndStandard(
+		std::shared_ptr<SourceGroupSettings> sourceGroupSettings,
+		QtProjectWizzardWindow* window);
+
+	// QtProjectWizzardContent implementation
+	virtual void populate(QGridLayout* layout, int& row) override;
+
+	virtual void load() override;
+	virtual void save() override;
+	virtual bool check() override;
+
+private:
+	std::shared_ptr<SourceGroupSettings> m_sourceGroupSettings;
+
+	QLabel* m_language;
+	QComboBox* m_standard;
+};
+
+#endif // QT_PROJECT_WIZZARD_CONTENT_LANGUAGE_AND_STANDARD