Remove option_identifier

It is no longer needed because we set the hash based on an actual
hash of the rom contents, so it is not based on the title field anymore.

Rom.py

@@ -974,8 +974,9 @@ def patch_rom(world, player, rom):
 
     # set rom name
     # 21 bytes
-    rom.name = bytearray('ER062%09d' % world.seed, 'utf8') + world.option_identifier(7, player).to_bytes(7, 'big')
-    assert(len(rom.name) == 21)
+    from Main import __version__
+    rom.name = bytearray('ER_{0}_{1:09}\0'.format(__version__,world.seed), 'utf8')
+    assert len(rom.name) <= 21
     rom.write_bytes(0x7FC0, rom.name)
 
     # Write title screen Code