Allow for optin in/out of the default option, and allow a default option other than "on"

[chriscct7]

The plugin should allow for either the default shift+enter to be either on or off for all users, and then hook into show_user_profile and create a field where users can be the opposite of the default.

For example, on EDD's site, there are some users who are not going to like it being on for everyone and they'll want to turn it off just for them. Even though its default on for all users, individual users should be able to opt out of it.

On the flip side, there should be a filter to allow a default of off, where users can then optin to using it.

I'll make a pr for this today/tomorrow and submit it. I think this will allow alot more people to use it.

[chriscct7]

I've decided to start this tomorrow

[pippinsplugins]

👍

[NikV]

Thanks for the help @chriscct7!