Allow Manual Default Values Entries

[githubsterer]

Developer TODO (don't remove)

• update documentation
  It's very difficult to fine tune the default settings values using only the slider. It would be much easier to have the ability to enter the number manually as well.

[sds100]

Yeah, that code for the settings page is archaic and needs rewriting, so fixing this issue won't be simple. It will happen when we eventually redo the entire settings screen :)