A couple of patches for PostgreSQL 64bit support

Hi, all,

I have posted a couple of patches with regard to 64bit environment
support to PATCHES ml.   It expands size of shared memory to 64bit space
and extends XID to 64bit.   Please take a look at it.

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Koichi Suzuki
Open Source Engineeering Departmeent,
NTT DATA Intellilink Corporation
Phone: +81-3-5566-9628  WWW: http://www.intellilink.co.jp
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