replace load with require
Privatize check_mountpoints and mount_store
back-fill test for MigrateDisk#long_running?
wrap test for .long_running? in describe
backfill test for .process
backfill tests for #migrate
extract mounting logic into mounter
#mount takes options
move Mounter to its own file
backfill mounter tests
Assert against Mounter#mount instead of backticking
remove temporary backticker left from refactoring