Fix download bandwidth for swift command.

We noticed a difference in download bandwidth while using
authentication details and pre-auth information for download.
Download using authentication details included authentication
time into the download bandwidth at each call of the function.
This time should have been excluded from download bandwidth.

This patch set is adding a timer variable to the client library.
That allows to accurately measure and store the time of each action.
Then while printing the download bandwith in the swift command
authentication time is excluded from bandwidth.

Change-Id: I63df9023e169f637f120ae9e25dac9c90a4e75a0
Fixes: bug #1197443
Merge "Fix download bandwidth for swift command."