varint - varint: create cast to get typmod working.

Log Message:
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create cast to get typmod working. fix alignment and storage of type

Modified Files:
--------------
varint:
varint.c (r1.3 -> r1.4)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/varint/varint/varint.c.diff?r1=1.3&r2=1.4)
varint.h (r1.3 -> r1.4)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/varint/varint/varint.h.diff?r1=1.3&r2=1.4)
varint.sql.in (r1.3 -> r1.4)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/varint/varint/varint.sql.in.diff?r1=1.3&r2=1.4)