IOConfig creates TimeMap independently of Schedule

Completely remove the dependency between Schedule and IOConfig. IOConfig
will generate its own instance of TimeMap, rather than relying on
Schedule to construction and keeping it alive.

opm/parser/eclipse/EclipseState/IOConfig/IOConfig.hpp

@@ -121,7 +121,7 @@ namespace Opm {
     public:
 
         IOConfig() = default;
-        explicit IOConfig( const Deck&, const Schedule& );
+        explicit IOConfig( const Deck& );
         explicit IOConfig( const std::string& input_path );
 
         int  getFirstRestartStep() const;