Adding license documentation to interface class docblocks.

src/Mod/Spreadsheet/App/PropertyColumnWidths.pyi

@@ -8,5 +8,7 @@ from Base.Persistence import Persistence
 )
 class PropertyColumnWidths(Persistence):
     """
+    Author: Eivind Kvedalen (eivind@kvedalen.name)
+    License: LGPL-2.1-or-later
     Internal spreadsheet object
     """

src/Mod/Spreadsheet/App/PropertyRowHeights.pyi

@@ -8,5 +8,7 @@ from Base.Persistence import Persistence
 )
 class PropertyRowHeights(Persistence):
     """
+    Author: Eivind Kvedalen (eivind@kvedalen.name)
+    License: LGPL-2.1-or-later
     Internal spreadsheet object
     """

src/Mod/Spreadsheet/App/PropertySheet.pyi

@@ -11,5 +11,7 @@ from Base.Persistence import Persistence
 )
 class PropertySheet(Persistence):
     """
+    Author: Eivind Kvedalen (eivind@kvedalen.name)
+    License: LGPL-2.1-or-later
     Internal spreadsheet object
     """

src/Mod/Spreadsheet/App/Sheet.pyi

@@ -11,6 +11,8 @@ from App.DocumentObject import DocumentObject
 )
 class Sheet(DocumentObject):
     """
+    Author: Eivind Kvedalen (eivind@kvedalen.name)
+    License: LGPL-2.1-or-later
     With this object you can manipulate spreadsheets
     """
 

src/Mod/Spreadsheet/Gui/ViewProviderSpreadsheet.pyi

@@ -12,6 +12,8 @@ from Gui.ViewProviderDocumentObject import ViewProviderDocumentObject
 )
 class ViewProviderSpreadsheet(ViewProviderDocumentObject):
     """
+    Author: Jose Luis Cercos Pita (jlcercos@gmail.com)
+    License: LGPL-2.1-or-later
     ViewProviderSheet class
     """