Recently, platform exposes new API to create LR with allocation
profile so that user can specify allocation pool for LoadBalancer.
Also update the feature support util since this feature is only
available on version 2.3 and after. This feature can be enabled
based on nsx version.
e.g. Create LR with LB SMALL allocation pool
allocation_pool = {
"allocation_pool_type": "LoadBalancerAllocationPool",
"allocation_size": "SMALL"}
create(..., allocation_pool=allocation_pool)
Change-Id: I55cd17a81b3ff6705345b170d15f26fc9a5b0f74
6982eed2b4