Bug#714864: [inventor] please transition from lesstif2 to motif

[Graham Inggs]

I  built two versions of inventor with the changes in Bug #718691; one 
with lesstif2-dev and the other with libmotif-dev.

I then tried running binaries from inventor-clients and inventor-demos 
built with lesstif2-dev against libinventor built with libmotif-dev.
I then repeated the tests with inventor-clients and inventor-demos built 
with libmotif-dev against libinventor build with lesstif2-dev.

In both cases the results were the same; the application frame and menu 
appeared as normal, but the GL window appeared as a 100 x 4 pixel area 
in the top left corner of the application frame.  There were no crashes.

None of the binaries were usable when libInventorXT.so.0.0.0 was not 
built with the same version of mo/less-tif.