* Move the observer implementation and the type definitions related with
it and helper functions to its own file.
* Cluster struct type is used as a key for a ObjectsMap type.
Observer struct type has a field of ObjectsMap.
Cluster has a field for project ID.
Observer processSegment method uses its ObjectMap field for tracking
objects.
However Observer processSegment clears the map once the projectID
diverges from the one kept in the Observer lastProjectID field, meaning
that it isn't needed to keep the projectID as part of the ObjectMap key.
For this reason, ObjectMap can use as a key just only the bucket name
and Cluster struct isn't needed.
Because of such change, the ObjectMap type has been renamed to a more
descriptive name.
* Make the types defined for this specific package not being exported.
* Create a constructor function for observer to encapsulate the map
allocation.
* Don't throw away the entirely buckets objects map when an empty one
is used to reuse part of the allocations.
Encapsulate the clearing up logic into a method.
* Make the analyzeProject function to be a method of observer.
* pkg/pg: Add new service function storage node
Add a new service function to the storage node piece store for deleting
pieces when satellites request them.
* storagenode/piecestore: Add endpoint to delete piece
Add a new endpoint to receive from trusted satellites to delete a piece.
* private/testplanet: Fix storagenode mock
Add to the storagenode mock the new endpoint method.
* proto.lock: Update it with the last protbuff changes
* storagenode/piecestore: Reuse test piece upload
Extract the repeated logic from several tests functions for uploading a
test piece to a test helper function.
* uplink/piecestore: Implement client side method
Implement the client side method of the new piecestore RPC function.
* storagenode/piecestore: Add test DeletePiece endpoint
Implement a test for the DeletePiece new endpoint method.
* update migration steps, add crdb support to testplanet
* add crdb support
* have jenkins run a bares bones crdb compat test
* skip crdb tests
* skip crdb tests
* fix root_piece_id column
* write crdb store to tmp dir
* escape
* satellite/console: Add X-Frame-Options and Referrer-Policy security headers
* Update to use CSP instead of XFO and include tardigrade.io
* Make FrameAncestors a config option
* Update satellite-config lock
* Make help text for FrameAncestors better
