Allow custom Evil states to keep the mark active

[LemonBreezes]

Hi. Currently Evil automatically enables visual-state whenever the mark is activated outside of visual-state, insert-state, and emacs-state.

As you can see, these 3 states are hard-coded into this function so the user has no way to create a custom evil state which should not enter visual-state automatically. This causes problems such as gridaphobe/evil-god-state#4.

I propose #1821 as a solution to this issue.