various: encapsulate all code in the olive namespace to avoid name collisions

Large-scale code cleanup. Also adds a license to the top of all files that were
missing it.

app/ui/style/style.cpp

@@ -30,6 +30,8 @@
 
 #include "ui/icons/icons.h"
 
+OLIVE_NAMESPACE_ENTER
+
 QList<StyleDescriptor> StyleManager::ListInternal()
 {
   QList<StyleDescriptor> style_list;
@@ -189,3 +191,5 @@ const QString &StyleDescriptor::path() const
 {
   return path_;
 }
+
+OLIVE_NAMESPACE_EXIT

app/ui/style/style.h

@@ -24,6 +24,10 @@
 #include <QSettings>
 #include <QWidget>
 
+#include "common/define.h"
+
+OLIVE_NAMESPACE_ENTER
+
 class StyleDescriptor {
 public:
   StyleDescriptor(const QString& name, const QString& path);
@@ -58,4 +62,6 @@ private:
   static void ParsePaletteColor(QSettings* ini, QPalette* palette, QPalette::ColorGroup group, const QString& role_name);
 };
 
+OLIVE_NAMESPACE_EXIT
+
 #endif // STYLEMANAGER_H