R/W differences not properly documented

[PennyJim]

The documentation can support describing different read and write types (as evidenced by LuaControl::force, but it's missing on a number of LuaEntity fields and only described in the description.

There might be more on other objects, but this is what I can easily find:

• LuaEntity::last_user
• LuaEntity::associated_player
• LuaEntity::render_player

[Therenas]

Thanks for the report, adjusted for the next release. There are probably more of these cases, but they are hard to sniff out without going over everything, and the format support for this kind of thing is very recent. So there are likely more such cases, which we would be happy to hear about if you run into any.