Issue/372 (#606)

* Add commandline argument that applies a Lua script to the configuration

include/openspace/engine/configuration.h

@@ -131,6 +131,8 @@ std::string findConfiguration(const std::string& filename = "openspace.cfg");
 
 Configuration loadConfigurationFromFile(const std::string& filename);
 
+void parseLuaState(Configuration& configuration);
+
 } // namespace openspace
 
 #endif // __OPENSPACE_CORE___CONFIGURATION___H__

include/openspace/engine/openspaceengine.h

@@ -121,6 +121,9 @@ public:
     void scheduleLoadSingleAsset(std::string assetPath);
     void toggleShutdownMode();
 
+    // On purpose, there is no function that returns a non-const reference to
+    // Configuration;  that guards us against anyone in the program changing the
+    // configuration values underneath our feet
     const Configuration& configuration() const;
 
     // Guaranteed to return a valid pointer