default periodic backup interval milliseconds to zero rather than null because PeriodicExportSetup.IntervalMilliseconds and PeriodicExportSetup.FullBackupIntervalMilliseconds are not nullable.
changed IntervalMilliseconds and FullBackupIntervalMilliseconds properties of PeriodicExportSetup to be nullable ints
Interval milliseconds can now be nullable value so reverting previous changeset
Don't use development storage when uploading periodic exports to Azure
Merge pull request #574 from nickchampion/master

default periodic backup interval milliseconds to zero rather than null b...