[entropy.tools] add dep_getcat function

libraries/entropy/tools.py

@@ -1690,6 +1690,11 @@ def dep_getkey(mydepx):
 
     return mydep
 
+def dep_getcat(mydep):
+    """
+    Extract package category from dependency.
+    """
+    return dep_getkey().split("/")[0]
 
 def dep_getcpv(mydep):
     """