libqof/qof

[Geert Janssens]

The recent cleanups in the qof code brought this to my attention again. The 
qof source is stored in src/libqof/qof/

No doubt this is a historical leftover from the time that Neil was working to 
make qof an independent library. Clearly GnuCash doesn't intend qof to be a 
separate library anymore. So I wonder, is there anything preventing us from 
moving the source from src/libqof/qof/ to src/qof/ ?

It's one small change to make the source tree structure a little more logical.

Geert