This commit doesn't change any behavior, just organize the code in
different way to make it easier to implement different Criterias
to include nodes. Today we use NodeID and Subnet based selection
but later Criteria can be extended with different kind of
placement rules (like geofencing).
The change nodeselection is used by segment allocaton (upload) and repair
and excludes nodes from an in-memory selection.
Resolves https://github.com/storj/storj/issues/4240
Change-Id: I0c1955fe16a045e3b76d7e50b2e1f4575a7ff095
Currently nodeselection package only contained state for uploads, move
these to a subpackage, such that we can make another "downloadselection"
for downloads. Then move selection logic from overlay to nodeselection.
Change-Id: I0fc42bcae3a29db2728dae9f3863b1e95bf5165b
* Deduplicate NodeID list prior to fetching IPs.
* Use NodeSelectionCache for fetching reliable IPs.
* Return number of segements, reliable pieces and all pieces.
Change-Id: I13e679caab275488b4037624b840a4068dad9589
Currently node selection cache is biased towards the same subnet. This
implements static node selection for distinct such that it selects with
equal probability subnets rather than id-s.
This is mostly a copy paste + modifications from previous node selection
state.
Change-Id: Ia5c0aaf68e7feca78fbbd7352ad369fcb77c3a05
