Update editor.less for page-header that influenced the gap between the nav and main classes

Signed-off-by: AntonyThorpe <antony.thorpe@budget12.com>
Adjust the layout by adding Layout Variables in layout.less

Signed-off-by: AntonyThorpe <antony.thorpe@budget12.com>
Change Navigation by adding media queries to classes

Signed-off-by: AntonyThorpe <antony.thorpe@budget12.com>
Make Footer element independent of main

Signed-off-by: AntonyThorpe <antony.thorpe@budget12.com>
Update Readme.md with the use of media queries in custom classes

Signed-off-by: AntonyThorpe <antony.thorpe@budget12.com>