More boost program-options cleanup
Change the CTable counts to doubles from ints.
An additional unsigned->double conversion for counts
Misc fixes, mostly float vs double

-- Use double, wherever space concern is not dominant
-- use score_t for those things that actually require a score_t
-- a remaining parse_options bug.
Use doubles, not floats ...

...when space-saving is not a concern
Merge pull request #690 from linas/remo

Use floating-point weights in CTable