Add option to disable /interrupt on AssistOff

[acastle]

This is to avoid a handful of undesirable side effects such as casters dismounting or bard's skipping songs while twisting. The new setting defaults to On, which will preserve the old behavior for anyone who doesn't want this change.

[RekkasGit]

Shouldn't this be "Interrupt on Assist Off"? or End Assist interrupt?

[RekkasGit]

Simply removed the interrupt as it made little sense to be put there, and made modifications to interrupts in general. Ty for bringing this to light tho as it made this a better project :)