Pytables support for FDPanel
add pytables branch to support FDPanel

this is on top of my previous fdpanel branch
supporting put/append/select of FDPanel to hdf5 tables (and makes selection a bit more generic, as store.select() now works).

FYI - the included FDPanel definitions (eg fdpanel.py) are v1 - so merge FDPanel (v2) first
 Then cherry pick this merge (eg only need pytables.py and tests and included examples)
