Cleanup of mostly asset files

- Fixes for all files
 - constexpr cleanup
 - Cosmetic changes
 - Remove punctuation from the end of messages

modules/spout/screenspacespout.cpp

@@ -36,7 +36,7 @@ namespace {
         "SpoutName",
         "Spout Sender Name",
         "This value explicitly sets the Spout receiver to use a specific name. If this "
-        "is not a valid name, an empty image is used."
+        "is not a valid name, an empty image is used"
     };
 
     constexpr openspace::properties::Property::PropertyInfo SelectionInfo = {
@@ -44,13 +44,13 @@ namespace {
         "Spout Selection",
         "This property displays all available Spout sender on the system. If one them is "
         "selected, its value is stored in the 'SpoutName' property, overwriting its "
-        "previous value."
+        "previous value"
     };
 
     constexpr openspace::properties::Property::PropertyInfo UpdateInfo = {
         "UpdateSelection",
         "Update Selection",
-        "If this property is trigged, the 'SpoutSelection' options will be refreshed."
+        "If this property is trigged, the 'SpoutSelection' options will be refreshed"
     };
 
     struct [[codegen::Dictionary(ScreenSpaceSpout)]] Parameters {