This patch removes pkg/util/mount completely, and replaces it with the
mount package now located at k8s.io/utils/mount. The code found at
k8s.io/utils/mount was moved there from pkg/util/mount, so the code is
identical, just no longer in-tree to k/k.
This patch moves fake.go to mount_fake.go, and follows to principle of
always returning a discrete type rather than an Interface. All callers
of "FakeMounter" are changed to instead use "NewFakeMounter()". The
FakeMounter "Log" struct member is changed to not be exported, and
instead only access through a new "GetLog()" method.
This patch cleans up pkg/util/mount/* and pkg/util/volume/* to always
use filepath.Join instead of path.Join. filepath.Join is preferred
because path.Join can have issues on Windows.
This commit adds a new volume manager in kubelet that synchronizes
volume mount/unmount (and attach/detach, if attach/detach controller
is not enabled).
This eliminates the race conditions between the pod creation loop
and the orphaned volumes loops. It also removes the unmount/detach
from the `syncPod()` path so volume clean up never blocks the
`syncPod` loop.
