#5 update menu creation code for Maya 8.0

[Andrew Chapman]

will probably need to update the menu creation MEL code
for Maya 8.0's customisable menu system (something like
`menuSet -addMenu pluginsMenu commonMenuSet;
updateMenuModeUI`)

Only an issue if, under v8.0 the Render Passes menu
isn't created when loading the plugin. I don't know if
this is a problem, just something to look out for when
v8.0 is released.