Pr/trails (#170)

* Implement new RenderableTrails as abstract base class
  - Implement RenderableTrailsOrbit and RenderableTrailsTrajectory as concrete instances
Remove old RenderableTrails and RenderableTrailsNew classes
Adapt mod files to the new structure

* Addressed Pull Request comments

include/openspace/properties/optionproperty.h

@@ -95,11 +95,11 @@ public:
     void addOption(int value, std::string desc);
 
     /**
-    * Appends options with vectors of values and descriptions
-    * \param values A std::vector<int> of values for the options
-    * \param descs A std::vector<string> of descriptions for each value
+    * Adds multiple options to the OptionProperty. Each value in the vector consists of
+    * an integer value and a string description.
+    * \param options Pairs of <option, description> that are added to the OptionProperty
     */
-    void addOptions(std::vector<int> values, std::vector<std::string> descs);
+    void addOptions(std::vector<std::pair<int, std::string>> options);
 
     /**
      * Returns the list of available options.

include/openspace/scene/translation.h

@@ -40,9 +40,12 @@ public:
 
     virtual ~Translation();
     virtual bool initialize();
+
     virtual glm::dvec3 position() const = 0;
     virtual void update(const UpdateData& data);
 
+    glm::dvec3 position(double time);
+
     static openspace::Documentation Documentation();
 };
 

include/openspace/util/updatestructures.h

@@ -46,6 +46,7 @@ struct UpdateData {
     TransformData modelTransform;
     double time;
     double delta;
+    bool timePaused;
     bool isTimeJump;
     bool doPerformanceMeasurement;
 };