FigureFactory edits

- subclass from `object`
- separated `create_ohlc()` into `_make_increasing()` and
`make_decreasing()` so the user can pass kwargs to the ‘increasing’ and
‘decreasing’ traces by defining `direction` as increasing or
decreasing. This keeps it consistent with `create_candlestick`
- make `_make_increasing` and
`_make_decreasing` static methods for ohlc and candlestick
- set `hovermode` to closest for ohlc

Author: cldougl