BGP routes with N-Multipath primary and 1-Protection backup gateway

The following enhancements are made to the Junos OS: 

• Support N+1 formation for BGP labelled unicast protection (LU). 
• Support N+1 formation for BGP PIC (IPv4, IPv6, LU). 
• Support for hetero-nexthops (ListNH) in such N+1 formations. 
• Support for KRT to defer fib-update if BGP-multipath is in progress. 
• Removed restriction to use delay-route-advertisement statement for IPv4 labeled-unicast. 
• Four new options import, install-address, no-install, andrib(inet.0|inet6.0) are added under the egress-te statement.
• A new configuration statement allow-protection is introduced to allow protection for multipath legs. To allow protection for multipath legs, use set allow-protection statement at the [edit protocols bgp multipath] hierarchy level.
  
• A new option always-wait-for-krt-drain is introducedunder delay-route-advertisement statement to make more-specific BGP-routes re-advertisement to wait for KRT-queue to drain. To configure this, use set always-wait-for-krt-drain at the [edit protocols bgp family inet unicast delay-route-advertisements] hierarchy level.