Merge pull request #849 from lakkatv/lakka

(Lakka) Responsive menu
(Menu) Refactor MENU_SETTINGS_NETPLAY_DELAY_FRAMES
Refactor away rarch_reinit_drivers
retroarch.c - cleanups
Refactor away rarch_main_idle_iterate
Refactor bsv movie free duplication
Refactor rarch_main_init
Refactor init_libretro_cbs_plain
Refactor take_screenshot_viewport
refactor rarch_main_clear_state
Refactors in retroarch.c to do with game reset
Refactor do_state_checks
(retroarch.c) Some refactors
Move state_slot variable from g_extern to g_settings
Refactor more code
Make rarch_load_state/rarch_save_state static functions
Refactor more functions - make more functions in retroarch.c static
that don't need to be public
Move check_netplay_flip to top of check_flip function
Make audio_sample_batch function static
Refactor audio_flush