Map some other function to the insert key

[Yuan Qi]

I think there is a consensus here that we should disable the insert key 
and leave the caps lock alone.

Yuan Qi wrote:
> I hope everyone is aware of this: 
> http://mpt.net.nz/archive/2005/04/11/ubuntu
> 
> One of the usability problems the author have mentioned in his article 
> is the fact that the insert key is mapped to the overwrite mode. Since 
> most computer users (even intermediate users) are not aware of this 
> mode, they will be confused and frustrated by the software's "buggy" 
> behaviour. Therefore, I suggest that we either map a different function 
> to this key or just disable it. Personally, I think the Paste function 
> is the most sensible function to be mapped to the insert key.
> 
>