change ValueWithComment from composition to Inheritance (simplifies code a lot)

code/utils/osg_statistics.py

@@ -1,4 +1,23 @@
 """
+Central place to calculate statistics about the entries. Used for updating the statistics.md file and the statistics page
+of the website.
+"""
 
-"""
 
+def get_build_systems(entries):
+    """
+    Given a list of entries, calculates statistics about the used build systems and returns the statistics as
+    sorted list of elements (build-system-name, occurence).
+    "n/a" is used if no build system was specified
+    """
+    build_systems = []
+    for entry in entries:
+        build_systems.extend(entry['Building'].get('Build system', ['n/a']))
+
+    unique_build_systems = set(build_systems)
+
+    build_systems_stat = [(l, build_systems.count(l)) for l in unique_build_systems]
+    build_systems_stat.sort(key=lambda x: str.casefold(x[0]))  # first sort by name
+    build_systems_stat.sort(key=lambda x: -x[1])  # then sort by occurrence (highest occurrence first)
+
+    return build_systems_stat