Add an option to remove the modal display in "interOxyAddIn()"

[earnaud]

interOxyAddIn() could be the best tool for R documentation ... if only it didn't interrupt the user every 1 second. This wastes all the effort. The modal could be only displayed once, or its content be reported as a paragraph in a headerPanel.

[yonicd]

The app was made years ago. I am sure it can be made better. You are welcome to make a PR to make it more user friendly,

In the past the whole interactive piece of sinew was supposed to get it's own package since it adds a lot of dependencies. So your suggestions will probably inform that package when I get around to it.