XD-236: Ported aggregate counter code from kodiak.

Added query method based on Joda time interval.
Currently only supports minute resolution.

XD-236: Rewrite aggregate count test with interval queries.
XD-236: Remove unused "DayCount" query option.

Accidentally left in. Not currently usable.
Added default output of gradle app plugin as deliverables
XD-315 Shell Startup Script
XD-365: enforce single PPC instance
Merge branch 'master' of github.com:SpringSource/spring-xd