Add support for hiding the native tab bar #18
Description
Should be a pref, something along the lines of glide.ui.hide_native_tabs: true or glide.ui.native_tabs: hide in case we might want to add more options in the future. Would also make sense to add it as an option in glide.o.
Then should just be applying the CSS described here:
https://github.com/mbnuqw/sidebery/wiki/Firefox-Styles-Snippets-(via-userChrome.css)#completely-hide-native-tabs-strip