Fix (hopefully) library dependency resolution.

Installing libs is now enabled, hardcoded.
Enable -Wall for all builds.
Fix many warnings and latent bugs.

logic/BaseInstance.cpp

@@ -30,7 +30,7 @@
 
 BaseInstance::BaseInstance(BaseInstancePrivate *d_in, const QString &rootDir,
 						   SettingsObject *settings_obj, QObject *parent)
-	: inst_d(d_in), QObject(parent)
+	: QObject(parent), inst_d(d_in)
 {
 	I_D(BaseInstance);
 	d->m_settings = settings_obj;

logic/InstanceFactory.cpp

@@ -133,16 +133,12 @@ InstanceFactory::InstCreateError InstanceFactory::copyInstance(BaseInstance *&ne
 	{
 	case NoLoadError:
 		return NoCreateError;
-	case UnknownLoadError:
-	{
-		rootDir.removeRecursively();
-		return UnknownCreateError;
-	}
 	case NotAnInstance:
-	{
 		rootDir.removeRecursively();
 		return CantCreateDir;
+	default:
+	case UnknownLoadError:
+		rootDir.removeRecursively();
+		return UnknownCreateError;	
 	}
-	}
-	;
 }

logic/JavaChecker.cpp

@@ -8,7 +8,7 @@ JavaChecker::JavaChecker(QObject *parent) : QObject(parent)
 {
 }
 
-int JavaChecker::performCheck(QString path)
+void JavaChecker::performCheck(QString path)
 {
 	if(QFile::exists(CHECKER_FILE))
 	{

logic/JavaChecker.h

@@ -17,7 +17,7 @@ class JavaChecker : public QObject
 	Q_OBJECT
 public:
 	explicit JavaChecker(QObject *parent = 0);
-	int performCheck(QString path);
+	void performCheck(QString path);
 
 signals:
 	void checkFinished(JavaCheckResult result);

logic/LegacyInstance.cpp

@@ -274,7 +274,6 @@ bool LegacyInstance::setIntendedVersionId(QString version)
 
 bool LegacyInstance::shouldUpdate() const
 {
-	I_D(LegacyInstance);
 	QVariant var = settings().get("ShouldUpdate");
 	if (!var.isValid() || var.toBool() == false)
 	{

logic/ModList.cpp

@@ -39,18 +39,26 @@ void ModList::startWatching()
 {
 	is_watching = m_watcher->addPath(m_dir.absolutePath());
 	if (is_watching)
+	{
 		QLOG_INFO() << "Started watching " << m_dir.absolutePath();
+	}
 	else
+	{
 		QLOG_INFO() << "Failed to start watching " << m_dir.absolutePath();
+	}
 }
 
 void ModList::stopWatching()
 {
 	is_watching = !m_watcher->removePath(m_dir.absolutePath());
 	if (!is_watching)
+	{
 		QLOG_INFO() << "Stopped watching " << m_dir.absolutePath();
+	}
 	else
+	{
 		QLOG_INFO() << "Failed to stop watching " << m_dir.absolutePath();
+	}
 }
 
 bool ModList::update()
@@ -64,7 +72,6 @@ bool ModList::update()
 	bool orderWasInvalid = false;
 
 	// first, process the ordered items (if any)
-	int currentOrderIndex = 0;
 	QStringList listOrder = readListFile();
 	for (auto item : listOrder)
 	{
@@ -363,6 +370,7 @@ QVariant ModList::headerData(int section, Qt::Orientation orientation, int role)
 	case 2:
 		return QString("Minecraft");
 	}
+	return QString();
 }
 
 Qt::ItemFlags ModList::flags(const QModelIndex &index) const

logic/OneSixInstance.cpp

@@ -235,7 +235,6 @@ void OneSixInstance::setShouldUpdate(bool val)
 
 bool OneSixInstance::shouldUpdate() const
 {
-	I_D(OneSixInstance);
 	QVariant var = settings().get("ShouldUpdate");
 	if (!var.isValid() || var.toBool() == false)
 	{

logic/OneSixUpdate.cpp

@@ -198,7 +198,6 @@ void OneSixUpdate::jarlibStart()
 
 	auto metacache = MMC->metacache();
 	QList<ForgeXzDownloadPtr> ForgeLibs;
-	bool already_forge_xz = false;
 	for (auto lib : libs)
 	{
 		if (lib->hint() == "local")

logic/lists/InstanceList.cpp

@@ -281,14 +281,6 @@ InstanceList::InstListError InstanceList::loadList()
 		auto &loader = InstanceFactory::get();
 		auto error = loader.loadInstance(instPtr, subDir);
 
-		switch (error)
-		{
-		case InstanceFactory::NoLoadError:
-			break;
-		case InstanceFactory::NotAnInstance:
-			break;
-		}
-
 		if (error != InstanceFactory::NoLoadError && error != InstanceFactory::NotAnInstance)
 		{
 			QString errorMsg = QString("Failed to load instance %1: ")