(Menu) Refactor menu_action_ok
(Menu) Add MENU_FILE_DIRECTORY type to switch
(Menu) Refactor common code in disp/rgui | rmenu | rmenu_xui
(Menu) Create two new types - MENU_FILE_SHADER and MENU_FILE_SHADER_PRESET
(Menu) Add more MENU_FILE_* types
(Settings data) refactor setting_data_*_setting functions
(Lakka) Fix subitems allocation
Merge pull request #967 from lakkatv/lakka

(Lakka) Fix subitems allocation
(Lakka) Savestate switching
Merge pull request #968 from lakkatv/lakka

(Lakka) Savestate switching
(Rsound) Build fix
(menu_common_backend.c) Refactor duplicate code
(Menu/Disp) Fix core name representation
(RMenu) Build fix
(Menu) menu_entries.c - Cast file_type to menu_file_type_t
Revert "(Settings data) refactor setting_data_*_setting functions"

This reverts commit 4438f7373207b54bc57db1c623fded59a6b94881.
(GLUI) GL based RGUI display driver clone
Merge pull request #969 from lakkatv/glui

(GLUI) GL based RGUI display driver clone
(GLUI) Fix disp_set_label
Merge pull request #970 from lakkatv/glui

(GLUI) Fix disp_set_label