[V6r9] FIX: SpaceTokenOccupancyPolicy

Policy that now takes into account absolute values for the space left:
10% free may represent 10GB or 100TB, depends on how large is the total space. Now it warns if free < 5TB and bans if < 10GB.

NOTE: this PR requires changing the types on one table in ResourceManagementDB

```
use ResourceManagementDB;
ALTER TABLE SpaceTokenOccupancyCache MODIFY Free DOUBLE NOT NULL Default 0;
ALTER TABLE SpaceTokenOccupancyCache MODIFY Guaranteed DOUBLE NOT NULL Default 0;
ALTER TABLE SpaceTokenOccupancyCache MODIFY Total DOUBLE NOT NULL Default 0;
```