unalias thigh_belt -> thigh_strap

BUR #10017 has been approved by @nonamethanks.

remove alias thigh_belt -> thigh_strap

Done in topic #6829 without explanation. There's a lot of thigh straps that aren't thigh belts.

The bulk update request #10017 (forum #211172) has been approved by @nonamethanks.

BUR #10545 has been approved by @nonamethanks.

create implication thigh_belt -> thigh_strap
create implication thigh_belt -> belt

Had to split this because the site was giving me error.

The bulk update request #10545 (forum #213817) has been approved by @nonamethanks.