pgsql: Add wrapper script around install.pl that calls buildenv.bat

Log Message:
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Add wrapper script around install.pl that calls buildenv.bat before doing
the install.

Dave Page

Added Files:
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pgsql/src/tools/msvc:
install.bat (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/tools/msvc/install.bat?rev=1.1&content-type=text/x-cvsweb-markup)