View Site button in the Admin should work even if Splash is installed in a subdirectory

[cbishop]

The View Site button should use #application.defaults.rootPath# to open the Splash root page.

Right now, if Splash is installed in a subdirectory, the View Site button opens the root page (/) of the site and doesn't go to the Splash subdirectory.

[raulriera]

This button should be dropped from everyone and just be a single button on the header