Add FreeCAD FCMacro extension to the python highlighting definition

Summary:
Add FreeCAD FCMacro extension to the python highlighting definition.
They are python scripts see:
https://www.freecadweb.org/wiki/Macros

Test Plan: Open an FCMacro file and it should have correct highlighting.

Reviewers: Framework: Syntax Highlighting, cullmann

Reviewed By: Framework: Syntax Highlighting, cullmann

Subscribers: cullmann, kwrite-devel, kde-frameworks-devel

Tags: Kate, Frameworks

Differential Revision: https://phabricator.kde.org/D27486