WL#1076: GIS: Fix WKB and big-endian problem

http://postgis.refractions.net/pipermail/postgis-users/2003-June/002651.html

* The MySQL code contains an assumption in the WKB handling that all WBK 
will be little endian. If you run MySQL spatial on a big endian machine 
(Sparc, PowerPC, PA-RISC) you will find things go amiss when you try to 
send WKB to little endian machines (x86), because your big endian 
machine will be creating invalid data (big endian data incorrectly 
flagged as little endian).