vmem: vmem_pool_create_in_region() address alignment up to Pagesize

-Update page protection in vmem_pool_create_in_region()
-Update man page
-Update Unit Tests.
Merge pull request #26 from spawlows/vmem-pool-create-in-region-addrs-allig

vmem: vmem_pool_create_in_region() address alignment up to Pagesize