Add roomscale shields

[DanDragonWolf]

Vivecraft needs to have a roomscale shield option. Some people, including myself, get confused and try to block by holding their shield in front of themselves instead of using the "use item" button, and would prefer to block physically instead of pressing a button to block.

[jrbudda]

this has been suggested many times and it's just not feasible with how minecraft combat works internally