Add fan control for as7116-54x
Modify sfputil.py to support sfp insert and remove events for as7116-54x
Modify port_config.nps to set port default admin down
Modify port_config.ini for add speed attr
Code format optimization like remove newline
Modify buffers_defaults_t0 and t1, change ingress_lossless_pool mode from dynamic to static
Add nephos_dac.nps and nephos_opt.nps for support difference dac and fiber module
* [updategraph] add support to use preset config instead of default minigraph
* Fix variable case
* Remove default minigraph case
* Remove default minigraphs and add default_sku files
