Revert "Issue #112: added navigation.html and searchbox.html back to html_sidebars setting"
Revert "Issue #112: added navigation.html and searchbox.html back to html_sidebars setting"

This reverts commit d395dd2f01e6ef9dc08182401d969ac64c551d32.

NifTK/NiftyNet,NifTK/NiftyNet,NifTK/NiftyNet,NifTK/NiftyNet