Takes into account the hierarchical structures of keymaps as well as wildcards (KM_ANY) in event definitions, user remaps (emulate numpad, action/select mouse buttons, ...) and event values that overlap (click, press and release)
For now, doesn't do anything other than print conflicts in the console.
As a result, I cleaned up a lot of keymaps that had double definitions, moved some keymap items in more appropriate places, fixed wrong definitions and removed kmi that were added for testing a long long time ago.
Out of all the remaining conflicts, after removing obvious non-issues, here's what remains: http://www.pasteall.org/9898