The global (exported) serverGeneration field is `unsigned long`, while
many other places copy it and compare it two other integer types, eg.
plain `int` (which is signed). Even if it's unlikely ever reaching such
high number of generations that it will ever make trouble, it's still
a good idea to clean this up and use the same type everywhere.
For clearity, introducing a typedef `x_server_generation_t` which is
used everywhere, instead of raw `unsigned long`.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
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