extracted job updating strategy into SerialMultiJobUpdater

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
added ParallelMultiJobUpdater

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
added serial option for job update

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
use BatchMultiJobUpdater when updating deployments

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
log whether SerialMultiJobUpdater or ParallelMultiJobUpdater is used

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
formatting
renamed NullRenderer to NullTaskLogRenderer
moved task tracking related classes into TaskTracking
formatting
indentation
extracted StageProgressBar used by EventLogRenderer
print some stages without progress bar
namespaced event log related classes in EventLog

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
hide big redis cube output in specs

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
prepare EventLog::Log to be thread friendly

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
refactor instance updater

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
use EventLog stage when updating jobs so that it is thread-safe

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
explicitly pass in EventLog stage to InstanceDeleter so that it is thread safe

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
changed default job update strategy to be serial

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>