Merge branch 'stable-5.7'

Merge branch 'stable-5.7'

* stable-5.7:
  Fix string format parameter for invalidRefAdvertisementLine
  WindowCache: add metric for cached bytes per repository
  pgm daemon: fallback to user and system config if no config specified
  WindowCache: add option to use strong refs to reference ByteWindows
  Replace usage of ArrayIndexOutOfBoundsException in treewalk
  Add config constants for WindowCache configuration options

Change-Id: I0538bcba259f7229790a602ac9de120464a1260d