Modify 'cuh' extension types in extensions.py

Updated the 'cuh' extension to include 'header' as a type.

Author: HagegeR

identify/extensions.py

@@ -52,7 +52,7 @@
     'csx': {'text', 'c#', 'c#script'},
     'cu': {'text', 'cuda'},
     'cue': {'text', 'cue'},
-    'cuh': {'text', 'cuda'},
+    'cuh': {'text', 'header', 'cuda'},
     'cxx': {'text', 'c++'},
     'cxxm': {'text', 'c++'},
     'cylc': {'text', 'cylc'},