Fiori launchpad Cache Buster Token

only add UI5 cache-busting token if provided via server-side configuration: oServerSideConfig.ui5CacheBusterToken

deactivated via ?sap-ushell-nocb=true

FioriLaunchpad.html is stored in BSP application /UI2/USHELL,

https://wiki.wdf.sap.corp/wiki/display/~I042416/155.+UI5+cache+buster+launchpad+debug

sServerSideConfig = “${SERVER-SIDE-CONFIG}”;