Clarify grab semantics

I've verified this with whot.
server: Allow overwriting a passive grab

whot says that any client can overwrite a passive grab, implicit or not
xeyes: Remove background pixmap

This was to test background pixmaps, which work absolutely fine.
Remove it so we don't have a bunch of flashing.
Fix AllowEvents processing
Don't send duplicate events

If we already sent an event as ownerEvents, we shouldn't also report it
as a grabbed event.
Fix count in iter_rectangles

The count describes how many rects are *after* this one.
Make sure to clear the path after clipping

This prevents leakage of the current path into the context.
Move pathToRegion to the toolkit utilities
Defer redrawing the frame until we get all of the expose events

To prevent unneeded redraws
Defer redrawing until we get all exposes for all toolkit clients

Holy crap this improves performance...
Raise the menu when opening it
Fix indentation

This bugged me.
Do some cosmetics work for the inspector
spacify inspector
Hack more on the inspector

Add a window highlight feature.
Move the server data into src/server