In 1.6.2 we were decoding inspect API response into interface{}.
time.Time fields were JSON encoded as RFC3339Nano in the response
and when decoded into interface{} they were just strings so the inspect
template treated them as just strings.
From 1.7 we are decoding into types.ContainerJSON and when the template
gets executed it now gets a time.Time and it's formatted as
2015-07-22 05:02:38.091530369 +0000 UTC.
This patch brings back the old behavior by typing time.Time fields
as string so they gets formatted as they were encoded in JSON -- RCF3339Nano
Signed-off-by: Antonio Murdaca <runcom@linux.com>