#66 Enrol Tab: Add Module

[graeme foster]

When a module is allocated it is added to the enrol tab
but in it's own sem branch in the tree, not the same
branch as an existing sem. So it ends up with, for example:

Sem 3
+ New Module
Sem 1
+ Old Module
+ Old Module
+ Old Module
Sem 3
+ Old Module
+ Old Module
+ Old Module
+ Old Module
Sem 5
+ Old Module
+ Old Module

[graeme foster]

Logged In: YES
user_id=1356778

There was a need for beginInsertRows() to be used.