#review-19743 @pallen
Add checks to make sure that sync CL is not bigger than head
If a p4.label or label is used with a number that is bigger than the head then this number is used everywhere.
This is causing P4_CHANGELIST to be incorrect but i can see this number can also be saved to a client object and that might be incorrect.
Add support for shelve to be a comma seperated list. (move from single int to string)
This means people can unshelve multiple changelists