ENG-6855: Refactor convenient methods in Permission so that there is only one
path that handles permission hierarchy mapping.
ENG-6855: Add permission inference.

SQL includes SQLREAD, DEFAULTPROC
SQLREAD includes DEFAULTPROCREAD
DEFAULTPROC includes DEFAULTPROCREAD
ADMIN includes everything

Only check for the appropriate permission in the permission policies.
ENG-6855: Fix broken tests.
Merge pull request #1753 from VoltDB/ENG-6855

ENG-6855: Add permission inference

r=akhanzode