* Port over some SP v2 bits
Specifically:
* Add too-large handling to Physical (Consul only for now)
* Contextify some identity funcs
* Update SP protos
* Add size limiting to inmem storage
* Use common abstraction for entity deletion
* Update group memberships before deleting entity
* Added test
* Fix return statements
* Update comment
* Cleanup member entity IDs while loading groups
* Added test to ensure that upgrade happens properly
* Ensure that the group gets persisted if upgrade code modifies it
* case insensitive identity names
* TestIdentityStore_GroupHierarchyCases
* address review feedback
* Use errwrap.Contains instead of errwrap.ContainsType
* Warn about duplicate names all the time to help fix them
* Address review feedback
* Start work on passing context to backends
* More work on passing context
* Unindent logical system
* Unindent token store
* Unindent passthrough
* Unindent cubbyhole
* Fix tests
* use requestContext in rollback and expiration managers
* return group memberships of entity during read
* Add implied group memberships to read response of entity
* distinguish between all, direct and inherited group IDs of an entity
* address review feedback
* address review feedback
* s/implied/inherited in tests
* external identity groups
* add local LDAP groups as well to group aliases
* add group aliases for okta credential backend
* Fix panic in tests
* fix build failure
* remove duplicated struct tag
* add test steps to test out removal of group member during renewals
* Add comment for having a prefix check in router
* fix tests
* s/parent_id/canonical_id
* s/parent/canonical in comments and errors
* porting identity to OSS
* changes that glue things together
* add testing bits
* wrapped entity id
* fix mount error
* some more changes to core
* fix storagepacker tests
* fix some more tests
* fix mount tests
* fix http mount tests
* audit changes for identity
* remove upgrade structs on the oss side
* added go-memdb to vendor