Merge pull request #1270 from lakkatv/xmb

(XMB) Display subsetting icons
menu_entries_cb: Remove unused variable
Merge pull request #1272 from lioncash/unused

menu_entries_cb: Remove unused variable
Simplify input_options function
Fixing Use Empty Path on directory settings
Merge pull request #1273 from jeapostrophe/master

Fixing iOS menu problems and cleaning code
Build fix
Generalize variable names
Implement other driver options too
Implement joypad driver settings options too
Small change
playlist.c - add warnings
Add content history dir and change 'retroarch-history.txt' to 'retroarch-content-history.txt'
Add early return to RARCH_CMD_HISTORY_INIT
Move rarch_main_command(RARCH_HISTORY_INIT) outside of check
for history list enable
(XMB) Fix another display bug