[wip/visp] Add setter for pose in vpMbtTracker.

This change is required when the display and the tracking
is done separately.

visp/distinfo

@@ -4,3 +4,4 @@ Size (visp-2.4.4-svn-20100810.tar.gz) = 1188625 bytes
 SHA1 (patch-a) = 0008fac5bc45106a88f9dadd1a579fe2150c035e
 SHA1 (patch-b) = ebc1d4deed6784603e886dcb95971cac5968bbaa
 SHA1 (patch-d) = 43433d7e4b52929a57454284fe3002c973cf8d9a
+SHA1 (patch-e) = d575b57b550cf8939b8b5244390ddec5a6fc2c3c

visp/patches/patch-e

+--- src/tracking/mbt/vpMbtTracker.h~	2010-08-13 18:46:21.000000000 +0900
++++ src/tracking/mbt/vpMbtTracker.h	2010-08-13 18:46:46.000000000 +0900
+@@ -128,6 +128,8 @@
+   */
+   inline void getPose(vpHomogeneousMatrix &cMo) const {cMo = this->cMo;}
+ 
++  inline void setPose(const vpHomogeneousMatrix& cMo) const {this->cMo=cMo;}
++
+   /*!
+    Get the camera paramters.
+