Add support for {delay=x} autotype token to slow down typing

[firecat53]

Perhaps adding support for {delay=x} as an autotype token can be used to slow down typing speed and reduce instances of items being mistyped as reported in #59.

[firecat53]

Note that this is different than the current {DELAY x} which just inserts a
pause between fields, not between characters.

[ndcontini]

I'd like to point out as someone who uses keepmenu + wtype, I regularly see instances where passwords are not correctly typed into websites, presumably because the speed at which wtype "types" the password is too high. I'd be really interested in adding this delay feature.

[firecat53]

I've been using ydotool for that reason. It seems like it should be easy to add by adding the -d option to wtype in type.py when the delay token is present or perhaps a global configuration value is set.