agent: Synchronize the read/writes to processes in container struct
agent: Synchronize the read/writes to processes in container struct

The processes map needs be protected against concurrent read and
writes. Several exec'ed processes for a container can update the
processes map of a container concurrently.

Fixes #76

Signed-off-by: Archana Shinde <047ac45ce396f63f3cf93ff43725668e736e0632@intel.com>

clearcontainers/agent,clearcontainers/agent