Keymap: add support for versioning keymaps

Write the Blender version into the keymap
so we can change defaults without breaking existing keymaps.

Based on patch by @erik85 with own additions.

release/scripts/modules/bl_keymap_utils/versioning.py

@@ -0,0 +1,49 @@
+# ##### BEGIN GPL LICENSE BLOCK #####
+#
+#  This program is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU General Public License
+#  as published by the Free Software Foundation; either version 2
+#  of the License, or (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software Foundation,
+#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+#
+# ##### END GPL LICENSE BLOCK #####
+
+# <pep8 compliant>
+
+# Update Blender version this key-map was written in:
+#
+# When the version is ``(0, 0, 0)``, the key-map being loaded didn't contain any versioning information.
+# This will older than ``(2, 92, 0)``.
+
+def keyconfig_update(keyconfig_data, keyconfig_version):
+    from bpy.app import version_file as blender_version
+    if keyconfig_version >= blender_version:
+        return keyconfig_data
+
+    # Version the key-map.
+    import copy
+    has_copy = False
+
+    # Default repeat to false.
+    if keyconfig_version <= (2, 92, 0):
+        # Only copy once.
+        if not has_copy:
+            keyconfig_data = copy.deepcopy(keyconfig_data)
+            has_copy = True
+
+        for _km_name, _km_parms, km_items_data in keyconfig_data:
+            for (_item_op, item_event, _item_prop) in km_items_data["items"]:
+                if item_event.get("value") == 'PRESS':
+                    # Unfortunately we don't know the 'map_type' at this point.
+                    # Setting repeat true on other kinds of events is harmless.
+                    item_event["repeat"] = True
+
+    return keyconfig_data