CRM-2214: Wrong calculation of "Opens" in Email Campaign Statistics
- fix last sync date
CRM-2214: Wrong calculation of "Opens" in Email Campaign Statistics
- store date string only
Merge pull request #40 from laboro/fix/CRM-2214_1.4

CRM-2214: Wrong calculation of "Opens" in Email Campaign Statistics
Merge remote-tracking branch 'remotes/dev/1.4' into 1.0