Feature/point cloud labels from csv (#2989)

* Add ability to load labels directly from CSV/SPECK for PointClouds

* Provide some more docs

* Update the example asset for point clouds

* Make both examples visible

* Some cleanup

* Apply suggestions from code review

Co-authored-by: Alexander Bock <alexander.bock@liu.se>

---------

Co-authored-by: Alexander Bock <alexander.bock@liu.se>

include/openspace/rendering/labelscomponent.h

@@ -47,6 +47,20 @@ namespace documentation { struct Documentation; }
 class LabelsComponent : public properties::PropertyOwner, public Fadeable {
 public:
     explicit LabelsComponent(const ghoul::Dictionary& dictionary);
+
+    /**
+     * Create a labels component from an already loaded dataset. That dataset should have
+     * a comment per point to be used for the labels.
+     *
+     * \param dictionary A dictionary with the other information used for constructing
+     *        the dataset
+     * \param dataset The dataset to create the labelset from, including xyz position and
+     *        a string to be used for the text.
+     * \param unit The unit to use when interpreting the point information in the dataset
+     */
+    explicit LabelsComponent(const ghoul::Dictionary& dictionary,
+        const dataloader::Dataset& dataset, DistanceUnit unit);
+
     ~LabelsComponent() override = default;
 
     dataloader::Labelset& labelSet();
@@ -76,7 +90,8 @@ private:
 
     glm::dmat4 _transformationMatrix = glm::dmat4(1.0);
 
-    // Properties
+    bool _createdFromDataset = false;
+
     properties::BoolProperty _enabled;
     properties::Vec3Property _color;
     properties::FloatProperty _size;