There's no need for the preprocessor checks for wx, since this is used in wx code. Also, this being a part of the InputCommon namespace is kind of wrong.
Minor other alterations that relate to above as well.
Also added the PanicAlertT version of alerts for some error messages that
use PanicAlert. We want the user to actually understand why the error
occurred.
Prior to this commit it was possible to assign the same keycode to more than one button.
ie. Say I assigned Open with the hotkey Ctrl+O; well, it was possible to also add it to another function as well, which leads to hotkey clashing.
Now, say I assign Open with Ctrl+O, but then assign that same hotkey to Refresh List; it will unbind the hotkey from Open and then assign it to refresh list.
