Make accelerator shortcuts order agnostic

[Blockyheadman]

When defining accelerator shortcuts, it depends on the order of how they're defined in order to work correctly.

For example, i have two shortcuts:

shortcut 1:
alt+`
shortcut 2:
alt+shift+`

if defined in that given order, the first shortcut shadows the shift modified one even though it's registered in the system.

My personal fix:
use a hashtable-like system where accelerators have generated lookups and can be searched for in linear time instead of a for loop.